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  • 1.
    Anderson, Mattias
    et al.
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Afewerki, Samson
    Berglund, Per
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Córdova, Armando
    Chemoenzymatic amination of alcohols by combining oxidation catalysts with transaminases in one potManuscript (preprint) (Other academic)
    Abstract [en]

    Chemoenzymatic methods for the amination of alcohols have been developed. The reactions were performed in a one-pot two-step fashion, where the alcohol starting material was first oxidized to the corresponding carbonyl compound and then subsequently converted to the amine product with an enzymatic system based on an amine transaminase. The enzyme system was able to operate in a water/organic solvent two-phase system in the presence of either a heterogeneous palladium(0) catalyst or a homogeneous copper(I) catalyst. High conversions to the product amines were achieved for a range of substituted benzyl alcohols and similar compounds, but unfortunately the use of aliphatic alcohols resulted in lower conversions and secondary alcohols could not be converted to the corresponding amines with this methodology.

  • 2.
    Anderson, Mattias
    et al.
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Afewerki, Samson
    Berglund, Per
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Cõrdova, Armando
    Total Synthesis of Capsaicin Analogues from Lignin-Derived Compounds by Combined Heterogeneous Metal, Organocatalytic and Enzymatic Cascades in One Pot2014In: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 356, no 9, p. 2113-2118Article in journal (Refereed)
    Abstract [en]

    The total synthesis of capsaicin analogues was performed in one pot, starting from compounds that can be derived from lignin. Heterogeneous palladium nanoparticles were used to oxidise alcohols to aldehydes, which were further converted to amines by an enzyme cascade system, including an amine transaminase. It was shown that the palladium catalyst and the enzyme cascade system could be successfully combined in the same pot for conversion of alcohols to amines without any purification of intermediates. The intermediate vanillyl-amine, prepared with the enzyme cascade system, could be further converted to capsaicin analogues without any purification using either fatty acids and a lipase, or Schotten-Baumann conditions, in the same pot. An aldol compound (a simple lignin model) could also be used as starting material for the synthesis of capsaicin analogues. Using l-alanine as organocatalyst, vanillin could be obtained by a retro-aldol reaction. This could be combined with the enzyme cascade system to convert the aldol compound to vanillylamine in a one-step one-pot reaction.

  • 3.
    Berglund, P.
    et al.
    Mid Sweden University.
    Holmquist, M.
    Hedenstrom, E.
    Hult, K.
    Hogberg, H. -E
    2-Methylalkanoic acids resolved by esterification catalysed by lipase from Candida rugosa: Alcohol chain length and enantioselectivity1993In: Tetrahedron Asymmetry, ISSN 09574166 (ISSN), Vol. 4, no 8, p. 1869-1878Article in journal (Refereed)
    Abstract [en]

    Enantiomerically pure (R)-2-methyldecanoic acid and (S)-2-methyl-1-decanol were prepared in a multi gram scale by esterification reactions catalysed by lipase from Candida rugosa. The enantiomeric ratios (E-values) were determined as a function of the chain length of the alcohol used as the complementary substrate in cyclohexane. In the resolution of 2-methyldecanoic acid the highest value (E = 37 ± 5) was obtained, when either 2-hexanol, 1-heptanol or 1-octanol were used. In contrast, when resolving 2-methyloctanoic acid, the E-values increased continually with increasing chain length of the alcohol used. 1-Hexadecanol gave the highest value: E > 100. The E-values were determined from the enantiomeric excess (ee) of the product at a conversion below 0.4. After two consecutive esterification reactions enantiomerically pure (R)-2-methyldecanoic acid, >99.8% ee, and after subsequent reduction of the ester produced, (S)-2-methyl-1-decanol, 96.7% ee, were obtained.

  • 4.
    Berglund, P.
    et al.
    Mid Sweden University.
    Holmquist, M.
    Hult, K.
    Hogberg, H. -E
    Alcohols as enantioselective inhibitors in a lipase catalysed esterification of a chiral acyl donor1995In: Biotechnology Letters, ISSN 01415492 (ISSN), Vol. 17, no 1, p. 55-60Article in journal (Refereed)
    Abstract [en]

    Increased reaction rates and increased enantioselectivities were observed with decreased concentrations of n-alkanols when resolving 2-methyldecanoic acid by esterification catalysed by immobilised lipase from Candida rugosa at controlled water activities in cyclohexane. The enantioselectivity was found to be independent of the water activity in the reaction medium at the n-heptanol concentrations investigated. However, when n-decanol was used as the acyl acceptor, not only the alcohol concentration but also the water activity in the reaction medium, influenced the enantioselectivity. The results obtained showed that the low enantioselectivity seen at a high alcohol concentration could be explained by the alcohol influencing the apparent V(max)(S) and V(max)(R) differently.

  • 5.
    Berglund, P.
    et al.
    University of Toronto, Canada.
    Stabile, M. R.
    Gold, M.
    Jones, J. B.
    Mitchinson, C.
    Bott, R. R.
    Graycar, T. P.
    Altering the specificity of subtilisin B. lentus by combining site-directed mutagenesis and chemical modification1996In: Bioorganic and Medicinal Chemistry Letters, ISSN 0960894X (ISSN), Vol. 6, no 21, p. 2507-2512Article in journal (Refereed)
    Abstract [en]

    The thiol side chain of the M222C mutant of the subtilisin from Bacillus lentus (SBL) has been chemically modified by methyl-, aminoethyl-, and sulfonatoethylthiosulfonate reagents. Introduction of charged residues into the active site of the enzyme reduced the catalytic efficiency with Suc-AAPF-pNA as the substrate, but resulted in better binding of sterically demanding boronic acid inhibitors.

  • 6.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Asymmetric Organic Synthesis with Enzymes: Edited by Vicente Gotor, Ignacio Alfonso and Eduardo Garcia-Urdiales2008In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 47, no 35, p. 6514-6515Article, book review (Other academic)
  • 7.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    BIO-AMINES: Searching for a Novel Approach to Biocatalytic Transaminations – a Vinnova Sponsored Project2009In: Book of abstracts, 2009Conference paper (Other academic)
  • 8.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Biocatalysis with Promiscuous Enzymes2007In: 2007 European BioPerspectives / [ed] Dechema, 2007Conference paper (Refereed)
  • 9.
    Berglund, Per
    KTH, Superseded Departments, Chemistry.
    Candida rugosa lipase as a catalyst in organic media: Enantioselectivity in kinetic resolutions of 2-methylalkanoic acids1995Doctoral thesis, comprehensive summary (Other academic)
  • 10.
    Berglund, Per
    KTH, Superseded Departments, Biochemistry and Biotechnology.
    Controlling lipase enantioselectivity for organic synthesis2001In: Biomolecular Engineering, ISSN 1389-0344, E-ISSN 1878-559X, Vol. 18, no 1, p. 13-22Article, review/survey (Refereed)
    Abstract [en]

    Lipases are used frequently as chiral catalysts in the synthesis of various fine chemicals and intermediates. The increasing need of compounds with high stereochemical purity requires catalysts with an improved and controlled performance. This overview emphasizes some important aspects for the control of lipase enantioselectivity and some examples where the enantioselectivity has been altered or reversed are highlighted. However, in several of these cases the complete explanation for the altered or reversed enantioselectivity remains unclear and needs to be solved. Three different strategies (engineering of the reaction medium, the substrate molecule, and the enzyme) for exploring lipase enantioselectivity at a molecular level are discussed and summarized. These three different approaches represent powerful tools for understanding the molecular basis for lipase enantioselective catalysis and can guide the rational improvement and tailoring of catalyst performance. By combining approaches from chemistry and biology much is learnt about the most important parameters controlling lipase enantioselectivity for organic synthesis.

  • 11.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Enzyme Catalytic Promiscuity and Rational Design2006In: Book of abstracts, 2006Conference paper (Refereed)
  • 12.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Enzymes Engineered for New Reactions - Novel Catalysts for Organic Synthesis2005In: Enzyme Technology / [ed] Pandey, A.; Webb, C.; Soccol, C. R.; Larroche, C., New Delhi: AsiaTech Publishers , 2005, p. 175-188Chapter in book (Refereed)
  • 13.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Hydrolases in Organic Synthesis: Regio- and Stereoselective Biotransformation: By Uwe T. Bornscheuer and Romas J. Kazlauskas2006In: ChemBioChem (Print), ISSN 1439-4227, E-ISSN 1439-7633, Vol. 7, no 8, p. 1280-Article, book review (Other academic)
  • 14.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    omega-Transaminases: Tailored for Chiral Amine Synthesis2010In: Biocat2010 / [ed] Ralf Grote, Garabed Antranikian, Hamburg, Germany: TuTech Verlag , 2010Conference paper (Refereed)
  • 15.
    Berglund, Per
    et al.
    KTH, Superseded Departments, Biotechnology.
    Branneby, Cecilia
    Svedendahl Humble, Maria
    KTH, School of Biotechnology (BIO), Biochemistry (closed 20130101).
    Carlqvist, Peter
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Physical Chemistry (closed 20110630).
    Magnusson, Anders
    Hult, Karl
    KTH, School of Biotechnology (BIO), Biochemistry (closed 20130101).
    Brinck, Tore
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Physical Chemistry (closed 20110630).
    Aldol and Michael additions catalyzed by a rationally redesigned hydrolytic enzyme2003In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 226, no 2, p. U155-U156Article in journal (Refereed)
  • 16.
    Berglund, Per
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Christiernin, M.
    Hedenström, E.
    Enantiorecognition of chiral acids by Candida rugosa lipase: Two substrate binding modes evidenced in an organic medium2001In: American Chemical Society Symposium Series (ACS), ISSN 0097-6156, E-ISSN 1947-5918, Vol. 776, p. 263-273Article in journal (Refereed)
    Abstract [en]

    We have identified the existence of different modes of binding the enantiomers of 2-methyl-branched carboxylic acids to a lipase active site by rational substrate engineering. Similar to hydrolysis, previously investigated, we have now evidence for differential binding modes in the Candida rugosa lipase-catalyzed esterifications in cyclohexane. The relevance of considering two different binding modes to understand lipase enantiorecognition is demonstrated by introducing bulky substituents on a chiral carboxylic acid which impose a different orientation of the substrate acyl chain in the active site of Candida rugosa lipase. With this substrate engineering approach based on molecular modeling it is thus possible to markedly alter the enantioselectivity of the lipase. Examples from hydrolysis and new results from esterifications in an organic solvent are presented and discussed.

  • 17.
    Berglund, Per
    et al.
    University of Toronto, Canada.
    DeSantis, Grace
    Stabile, Michele R.
    Shang, Xiao
    Gold, Marvin
    Bott, Richard R.
    Graycar, Thomas P.
    Lau, Tony Hing
    Mitchinson, Colin
    Jones, J. Bryan
    Chemical Modification of Cysteine Mutants of Subtilisin Bacillus lentus Can Create Better Catalysts Than the Wild-Type Enzyme1997In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 119, no 22, p. 5265-5266Article in journal (Refereed)
  • 18.
    Berglund, Per
    et al.
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Hedenstrom, E
    Hult, K
    Controlling lipase enantioselectivity for organic synthesis2000In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 219, no 1, p. U219-U219Article in journal (Refereed)
  • 19.
    Berglund, Per
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Hedenström, Erik
    Mid Sweden university.
    Preparation of 2-, 3-, and 4-methylcarboxylic acids and the corresponding alcohols of high enantiopurity by lipase-catalyzed esterification2001In: Enzymes in Nonaqueous Solvents: Methods and Protocols / [ed] Vulfson, E. N.; Halling, P. J.; Holland, H. L., Totowa: Humana Press , 2001, p. 307-317Chapter in book (Refereed)
  • 20.
    Berglund, Per
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Holmquist, M.
    Hult, K.
    Reversed enantiopreference of Candida rugosa lipase supports different modes of binding enantiomers of a chiral acyl donor1998In: Journal of Molecular Catalysis - B Enzymatic, ISSN 13811177 (ISSN), Vol. 5, no 1-4, p. 283-287Article in journal (Refereed)
    Abstract [en]

    Molecular modelling identifies two different productive modes of binding the enantiomers of a 2-methyldecanoic acid ester to the active site of Candida rugosa lipase (CRL). The fast reacting S-enantiomer occupies the previously identified acyl-binding tunnel of the enzyme, whereas the R- enantiomer leaves the tunnel empty. The modelling suggested that if both enantiomers were forced to bind to the active site leaving the tunnel empty, the enzyme would reverse its enantiopreference to become R-enantioselective. To test this hypothesis, we designed a structural analogue to 2- methyldecanoic acid, 2-methyl-6-(2-thienyl)hexanoic acid, which was expected to be too bulky to fit its acyl moiety into the acyl-binding tunnel. The CRL- catalysed hydrolysis of the ethyl ester of this substrate resulted in the preferential conversion of the R-enantiomer as predicted by molecular modelling. This represents the first kinetic evidence supporting the existence of two different modes of binding the enantiomers of a 2- methyldecanoic acid ester to the active site of CRL. We have shown that a rational 3D based approach in combination with substrate engineering can be used to predict and control the stereochemical outcome of a lipase catalysed reaction.

  • 21.
    Berglund, Per
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Hult, Karl
    KTH, School of Biotechnology (BIO), Biochemistry.
    Biocatalytic synthesis of enantiopure compounds using lipases: Chapter 212000In: Stereoselective Biocatalysis / [ed] Patel, R. N., New York: Marcel Dekker, 2000, p. 633-657Chapter in book (Refereed)
  • 22.
    Berglund, Per
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry (closed 20130101).
    Högfeldt, Anna-Karin
    KTH, School of Education and Communication in Engineering Science (ECE), Learning.
    Karlsson, Sara
    KTH.
    Klasén, Ida
    KTH, School of Education and Communication in Engineering Science (ECE).
    Sandberg, Teresia
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Utvärdering för utveckling: KTH:s samtliga utbildningar under belysning2011Conference paper (Other academic)
  • 23.
    Berglund, Per
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Park, S.
    Strategies for altering enzyme reaction specificity for applied biocatalysis2005In: Current organic chemistry, ISSN 1385-2728, E-ISSN 1875-5348, Vol. 9, no 4, p. 325-336Article in journal (Refereed)
    Abstract [en]

    The fact that many enzymes have broad substrate specificity has been a property, of fundamental importance for the widespread applications of enzymes in synthetic chemistry. Many enzymes can, in addition, catalyze completely different reactions compared to their natural ones. The possibility of using molecular biology techniques to control Such catalytic plasticity of enzymes in order to establish completely new reaction specificity in the active site is the topic for this review. The examples are subdivided according to six different approaches used (i - vi) for engineering of the reaction specificity. The first approach (i) is the random method of directed evolution to achieve new reaction specificity. Other approaches involve strategies where tire reaction specificity of a known enzyme is implemented into another, closely related, enzyme by substituting key amino acid residues selected either by (ii) sequence or (iii) structural overlap of the two enzymes. Yet other approaches involve substitution of key amino acid residues to introduce new reaction specificity without comparing with a template enzyme (iv) and the introduction of a complete catalytic machinery (v). The final approach is the introduction of an active site into a non-catalytic protein (vi). These six different approaches for altering the reaction chemistry of enzymes each represent a powerful tool for controlling the catalytic plasticity or enzymes. The prospect for these altered enzymes as catalysts in synthetic chemistry is very large although examples of practical use are rare and still challenging. The progress in the area of altering enzyme reaction specificity will result in a Continued development towards the goal of creating tailor-made enzymes for synthetic chemistry.

  • 24.
    Berglund, Per
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry (closed 20130101).
    Svedendahl Humble, Maria
    Branneby, Cecilia
    7.18 C-X Bond Formation: Transaminases as Chiral Catalysts: Mechanism, Engineering, and Applications2012In: Comprehensive Chirality, Elsevier, 2012, Vol. 7, p. 390-401Chapter in book (Refereed)
    Abstract [en]

    Enantiomerically pure amines and amino acids are important building blocks in academic research as well as in industrial-scale chemical production. Transaminases are versatile enzymes providing access to such compounds of high enantiomeric excess. This chapter illustrates the available strategies with transaminases such as kinetic resolution or stereoselective synthesis and highlights many successful examples for amino acid and chiral amines synthesis. There are some known challenges linked to the use of transaminases, for example in terms of unfavorable equilibria and inhibition. Several successful examples to overcome these limitations are presented. Also, the classification of transaminases, mechanistic details, and various strategies for optimization are discussed.

  • 25.
    Berglund, Per
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Svedendahl, Maria
    KTH, School of Biotechnology (BIO), Biochemistry.
    Engelmark Cassimjee, Karim
    KTH, School of Biotechnology (BIO), Biochemistry.
    Branneby, Cecilia
    Cambrex Karlskoga AB.
    Abedi, Vahak
    AstraZeneca.
    Wells, Andrew
    AstraZeneca.
    Federsel, Hans-Jürgen
    AstraZeneca.
    Omega-Transaminases Redesigned for Chiral Amine Synthesis2011In: BIT Life Sciences’ 2nd Symposium on Enzymes & Biocatalysis, Dalian, China: BIT Life Sciences , 2011Conference paper (Refereed)
  • 26.
    Berglund, Per
    et al.
    KTH, Superseded Departments, Biotechnology.
    Vallikivi, I.
    Fransson, Linda
    KTH, Superseded Departments, Biotechnology.
    Dannacher, H.
    Holmquist, Mats
    KTH, Superseded Departments, Biotechnology.
    Martinelle, Mats
    KTH, Superseded Departments, Biotechnology.
    Björkling, F.
    Parve, O.
    Hult, Karl
    KTH, Superseded Departments, Biotechnology.
    Switched enantiopreference of Humicola lipase for 2-phenoxyalkanoic acid ester homologs can be rationalized by different substrate binding modes1999In: Tetrahedron: asymmetry, ISSN 0957-4166, E-ISSN 1362-511X, Vol. 10, no 21, p. 4191-4202Article in journal (Refereed)
    Abstract [en]

    Humicola lanuginosa lipase was used for enantioselective hydrolyses of a series of homologous 2-phenoxyalkanoic acid ethyl esters. The enantioselectivity (E-value) of the enzyme changed from an (R)-enantiomer preference for the smallest substrate, 2-phenoxypropanoic acid ester, to an (S)-enantiomer preference for the homologous esters with longer acyl moieties. The E-values span the range from E=13 (R) to E=56 (S). A molecular modeling study identified two different substrate-binding modes for each enantiomer. We found that the enantiomers favored different modes. This discovery provided a model that offered a rational explanation for the observed switch in enantioselectivity. (C) 1999 Elsevier Science Ltd. All rights reserved.

  • 27.
    Berglund, Per
    et al.
    Mid Sweden University.
    Vörde, Carin
    Hogberg, Hans-Erik
    Esterification of 2-methylalkanoic acids Catalysed by Lipase from Candida rugosa: Enantioselectivity as a Function of water Activity and Alcohol Chain Length1994In: Biocatalysis and Biotransformation, ISSN 1024-2422, E-ISSN 1029-2446, Vol. 9, no 1-4, p. 123-130Article in journal (Refereed)
  • 28.
    Branneby, Cecilia
    et al.
    KTH, Superseded Departments, Biotechnology.
    Carlqvist, Peter
    KTH, Superseded Departments, Chemistry.
    Hult, Karl
    KTH, Superseded Departments, Biotechnology.
    Brinck, Tore
    KTH, Superseded Departments, Chemistry.
    Berglund, Per
    KTH, Superseded Departments, Biotechnology.
    Aldol Additions with Mutant Lipase: Analysis by Experiments and Theoretical Calculations2004In: Journal of Molecular Catalysis B: Enzymatic, ISSN 1381-1177, E-ISSN 1873-3158, Vol. 31, no 4-6, p. 123-128Article in journal (Refereed)
    Abstract [en]

    A Ser105Ala mutant of Candida antarctica lipase B has previously been shown to catalyze aldol additions. Quantum chemical calculations predicted a reaction rate similar to that of natural enzymes, whereas experiments showed a much lower reaction rate. Molecular dynamics simulations, presented here, show that the low reaction rate is a consequence of the low frequencies of near attack complexes in the enzyme. Equilibrium was also considered as a reason for the slow product formation, but could be excluded by performing a sequential reaction to push the reaction towards product formation. In this paper, further experimental results are also presented, highlighting the importance of the entire active site for catalysis.

  • 29. Branneby, Cecilia
    et al.
    Carlqvist, Peter
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Physical Chemistry (closed 20110630).
    Hult, Karl
    KTH, School of Biotechnology (BIO), Biochemistry (closed 20130101).
    Brinck, Tore
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Physical Chemistry (closed 20110630).
    Berglund, Per
    KTH, Superseded Departments, Biotechnology.
    Rational redesign of a lipase to an aldolase2003In: Biochemistry, ISSN 0006-2960, E-ISSN 1520-4995, Vol. 42, no 28, p. 8633-8633Article in journal (Refereed)
  • 30.
    Branneby, Cecilia
    et al.
    KTH, Superseded Departments, Biotechnology.
    Carlqvist, Peter
    KTH, Superseded Departments, Chemistry.
    Magnusson, Anders
    KTH, Superseded Departments, Biotechnology.
    Hult, Karl
    KTH, Superseded Departments, Biotechnology.
    Brinck, Tore
    KTH, Superseded Departments, Chemistry.
    Berglund, Per
    KTH, Superseded Departments, Biotechnology.
    Carbon-Carbon Bonds by Hydrolytic Enzymes2003In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 125, no 4, p. 874-875Article in journal (Refereed)
    Abstract [en]

    Enzymes are efficient catalysts in synthetic chemistry, and their catalytic activity with unnatural substrates in organic reaction media is an area attracting much attention. Protein engineering has opened the possibility to change the reaction specificity of enzymes and allow for new reactions to take place in their active sites. We have used this strategy on the well-studied active-site scaffold offered by the serine hydrolase Candida antarctica lipase B (CALB, EC 3.1.1.3) to achieve catalytic activity for aldol reactions. The catalytic reaction was studied in detail by means of quantum chemical calculations in model systems. The predictions from the quantum chemical calculations were then challenged by experiments. Consequently, Ser105 in CALB was targeted by site-directed mutagenesis to create enzyme variants lacking the nucleophilic feature of the active site. The experiments clearly showed an increased reaction rate when the aldol reaction was catalyzed by the mutant enzymes as compared to the wild-type lipase. We expect that the new catalytic activity, harbored in the stable protein scaffold of the lipase, will allow aldol additions of substrates, which cannot be reached by traditional aldolases

  • 31.
    Branneby, Cecilia
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Park, Seongsoon
    KTH, School of Biotechnology (BIO), Biochemistry.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Investigation of Substrate Specificity of Geobacillus stearothermophilus Alanine RacemaseManuscript (preprint) (Other academic)
  • 32.
    Branneby, Cecilia
    et al.
    Cambrex Karlskoga AB.
    Svedendahl, Maria
    KTH, School of Biotechnology (BIO), Biochemistry.
    Hult, Karl
    KTH, School of Biotechnology (BIO), Biochemistry.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Lipase-Catalyzed Aldol and Michael-Type Reactions2006Conference paper (Refereed)
  • 33.
    Branneby, Cecilia
    et al.
    Cambrex Karlskoga AB.
    Svedendahl, Maria
    KTH, School of Biotechnology (BIO), Biochemistry.
    Hult, Karl
    KTH, School of Biotechnology (BIO), Biochemistry.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Lipase-Catalyzed Aldol and Michael-Type Reactions2005In: Book of abstracts, 2005Conference paper (Refereed)
  • 34. Bydén, M.
    et al.
    Edlund, H.
    Berglund, P.
    Mid Sweden university.
    Lindström, B.
    Phase equilibria in two aqueous chiral surfactant systems1997In: Progress in Colloid and Polymer Science, ISSN 0340-255X, E-ISSN 1437-8027, Vol. 105, p. 360-364Article in journal (Refereed)
    Abstract [en]

    In this study, we present the binary phase diagrams of the pure (R)- and the racemic aqueous sodium-2-methyldecanoate surfactant systems. The latter is a 1:1 mixture of the pure (S)- and pure (R)-form. The systems were investigated using crossed polaroids, polarizing optical microscope and 2HNMR splittings. Both systems form a micellar phase, followed by a hexagonal, some intermediate phase and a large cubic phase. At even higher concentrations, the 2HNMR studies showed larger quadrupolar splittings up to 1200 Hz, due to a lamellar phase. The intermediate phase was in both cases very narrow, and extended up to > 23°C in the racemic system and up to 30°C in the pure (R)-system. The similarity between these two binary phase diagrams indicates that the change in molecular packing is so small that it does not drastically affect the phase behavior. The Krafft temperature in the micellar phase in both systems is 1°C, which is very low compared to that of unsubstituted alkanoates with the same chain length.

  • 35.
    Carlqvist, Peter
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Physical Chemistry.
    Svedendahl, Maria
    KTH, School of Biotechnology (BIO), Biochemistry.
    Branneby, Cecilia
    KTH, School of Biotechnology (BIO), Biochemistry.
    Hult, Karl
    KTH, School of Biotechnology (BIO), Biochemistry.
    Brinck, Tore
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Physical Chemistry.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Exploring the Active-Site of a Rationally Redesigned Lipase for Catalysis of Michael-Type Additions2005In: ChemBioChem (Print), ISSN 1439-4227, E-ISSN 1439-7633, Vol. 6, p. 331-336Article in journal (Refereed)
    Abstract [en]

    Michael-type additions of various thiols and alpha,beta-unsaturated carbonyl compounds were performed in organic solvent catalyzed by wild-type and a rationally redesigned mutant of Candida antarctica lipase B. The mutant locks the nucleophilic serine 105 in the active-site; this results in a changed catalytic mechanism of the enzyme. The possibility of utilizing this mutant for Michael-type additions was initially explored by quantum-chemical calculations on the reaction between acrolein and methanethiol in a model system. The model system was constructed on the basis of docking and molecular-dynamics simulations and was designed to simulate the catalytic properties of the active site. The catalytic system was explored experimentally with a range of different substrates. The k(cat) values were found to be in the range of 10(-3) to 4 min(-1), similar to the values obtained with aldolase antibodies. The enzyme proficiency was 10(7). Furthermore, the Michael-type reactions followed saturation kinetics and were confirmed to take place in the enzyme active site.

  • 36.
    Cassimjee, Karim Engelmark
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Humble, Maria Svedendahl
    KTH, School of Biotechnology (BIO), Biochemistry.
    Land, Henrik
    KTH, School of Biotechnology (BIO), Biochemistry.
    Abedi, Vahak
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Chromobacterium violaceum omega-transaminase variant Trp60Cys shows increased specificity for (S)-1-phenylethylamine and 4 '-substituted acetophenones, and follows Swain-Lupton parameterisation2012In: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 10, no 28, p. 5466-5470Article in journal (Refereed)
    Abstract [en]

    For biocatalytic production of pharmaceutically important chiral amines the.-transaminase enzymes have proven useful. Engineering of these enzymes has to some extent been accomplished by rational design, but mostly by directed evolution. By use of a homology model a key point mutation in Chromobacterium violaceum omega-transaminase was found upon comparison with engineered variants from homologous enzymes. The variant Trp60Cys gave increased specificity for (S)-1-phenylethylamine (29-fold) and 4'-substituted acetophenones (similar to 5-fold). To further study the effect of the mutation the reaction rates were Swain-Lupton parameterised. On comparison with the wild type, reactions of the variant showed increased resonance dependence; this observation together with changed pH optimum and cofactor dependence suggests an altered reaction mechanism.

  • 37.
    Cassimjee, Karim Engelmark
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Humble, Maria Svedendahl
    KTH, School of Biotechnology (BIO), Biochemistry.
    Miceli, Valentina
    KTH, School of Biotechnology (BIO), Biochemistry.
    Colomina, Carla Granados
    KTH, School of Biotechnology (BIO), Biochemistry.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Active Site Quantification of an omega-Transaminase by Performing a Half Transamination Reaction2011In: ACS CATAL, ISSN 2155-5435, Vol. 1, no 9, p. 1051-1055Article in journal (Refereed)
    Abstract [en]

    Measurement of the active enzyme fraction in a given enzyme preparation is a requirement for accurate kinetic measurements and activity comparisons of, for example, engineered mutants. omega-Transaminases, enzymes capable of interconverting ketones and amines by use of pyridoxal-5'-phosphate (PIP), can be used for the production of pharmaceutically important chiral amines but are subject to engineering to meet the practical requirements in synthesis reactions. Therefore, an active site quantification method is needed. Such a method was developed by quantifying the amount of consumed substrate in a virtually irreversible half transamination reaction. (S)-1-phenylethylamine was converted to acetophenone, while the holo enzyme (E-PLP) was converted to apo enzyme with bound pyridoxamine-5'-phosphate (E:PMP). Further, the mass of active enzyme was correlated to the absorbance of the holo enzyme to achieve a direct measurement method. The active Chromobacterium violaceum omega-transaminase with bound PLP can be quantified at 395 nm with an apparent extinction coefficient of 8.1 mM(-1) cm(-1).

  • 38.
    Cassimjee, Karim Engelmark
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Kourist, Robert
    Lindberg, Diana
    Larsen, Marianne Wittrup
    KTH, School of Biotechnology (BIO), Biochemistry.
    Thanh, Nguyen Hong
    KTH, School of Biotechnology (BIO), Biochemistry.
    Widersten, Mikael
    Bornscheuer, Uwe T.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    One-step enzyme extraction and immobilization for biocatalysis applications2011In: Biotechnology Journal, ISSN 1860-6768, E-ISSN 1860-7314, Vol. 6, no 4, p. 463-469Article in journal (Refereed)
    Abstract [en]

    An extraction/immobilization method for His(6)-tagged enzymes for use in synthesis applications is presented. By modifying silica oxide beads to be able to accommodate metal ions, the enzyme was tethered to the beads after adsorption of Co(II). The beads were successfully used for direct extraction of C. antarctica lipase B (CalB) from a periplasmic preparation with a minimum of 58% activity yield, creating a quick one-step extraction-immobilization protocol. This method, named HisSi Immobilization, was evaluated with five different enzymes [Candida antarctica lipase B (CalB), Bacillus subtilis lipase A (BslA), Bacillus subtilis esterase (BS2), Pseudomonas fluorescence esterase (PFE), and Solanum tuberosum epoxide hydrolase 1 (StEH1)]. Immobilized CalB was effectively employed in organic solvent (cyclohexane and acetonitrile) in a transacylation reaction and in aqueous buffer for ester hydrolysis. For the remaining enzymes some activity in organic solvent could be shown, whereas the non-immobilized enzymes were found inactive. The protocol presented in this work provides a facile immobilization method by utilization of the common His 6 tag, offering specific and defined means of binding a protein in a specific location, which is applicable for a wide range of enzymes.

  • 39.
    Cassimjee, Karim Engelmark
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Trummer, Martin
    KTH, School of Biotechnology (BIO), Biochemistry.
    Branneby, Cecilia
    KTH, School of Biotechnology (BIO), Biochemistry.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Silica-immobilized His(6)-tagged enzyme: Alanine racemase in hydrophobic solvent2008In: Biotechnology and Bioengineering, ISSN 0006-3592, E-ISSN 1097-0290, Vol. 99, no 3, p. 712-716Article in journal (Refereed)
    Abstract [en]

    A new immobilization method for enzymes is presented to facilitate synthetic applications in aqueous as well as organic media. The enzyme Alanine racemase (AlaR) from Geobacillus stearothermophilus was cloned, overexpressed and then immobilized on a silica-coated thin-layer chromatography plate to create an enzyme surface. The enzyme, fused to a His(6)-tag at its N-terminal, was tethered to the chemically modified silica-coated TLC plate through cobalt ions. The immobilized enzyme showed unaltered kinetic parameters in small-scale stirred reactions and retained its activity after rinsing, drying, freezing or immersion in n-hexane. This practical method is a first step towards a general immobilization method for synthesis applications with any enzyme suitable for His(6)-tagging.

  • 40.
    Chen, Shan
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Berglund, Per
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Svedendahl Humble, Maria
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    The effect of phosphate group binding cup coordination on the stability of the amine transaminase from Chromobacterium violaceum2018In: Molecular Catalysis, ISSN 2468-8231, Vol. 446, p. 115-123Article in journal (Refereed)
    Abstract [en]

    The amine transaminase from Chromobacterium violaceum (Cv-ATA) is a pyridoxal-5’-phosphate (PLP)dependent enzyme. The biological activity of this enzyme requires the formation of a holo homo dimer.The operational stability of Cv-ATA is, however, low due to dimer dissociation. At the enzyme dimeric interface, two phosphate group binding cups (PGBC) are located. Each cup coordinates the phosphate group of PLP by hydrogen bonds originating from both subunits. Hypothetically, molecular coordination of phosphate groups (PLP or free inorganic phosphate) into the PGBC can affect both dimer stabilization and enzyme activity. To test this assumption, the influence of phosphate (as a functional group in PLP or as free inorganic anions) on the stability and activity of Cv-ATA was explored by various biophysical techniques. The results show that Cv-ATA has a relatively low affinity towards PLP, which results in an excess of apo dimeric enzyme after enzyme purification. Incubation of the apo dimer in buffer solution supplemented with PLP restored the active holo dimer. The addition of PLP or inorganic phosphate into the enzyme storage solutions protected Cv-ATA from both chemical and long term storage unfolding. The use of phosphate buffer leads to faster inactivation of the holo enzyme, compared to the use of HEPES buffer. These results open up for new perspectives on how to improve the stability of PLP-dependent enzymes.

  • 41.
    Chen, Shan
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Berglund, Per
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Svedendahl, Maria
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Characterization of the operational stability of a transaminase from Vibrio fluvialisManuscript (preprint) (Other academic)
  • 42.
    Chen, Shan
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Berglund, Per
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Svedendahl, Maria
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Inactivation pathway underlying the operational instability of an amine transaminase from Chromobacterium violaceumManuscript (preprint) (Other academic)
  • 43.
    Chen, Shan
    et al.
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Land, Henrik
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Svedendahl Humble, Maria
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Stabilization of an amine transaminase for biocatalysis2016In: Journal of Molecular Catalysis B: Enzymatic, ISSN 1381-1177, E-ISSN 1873-3158, Vol. 124, p. 20-28Article in journal (Refereed)
    Abstract [en]

    The amine transaminase from Chromobacterium violaceum (Cv-ATA) is a well-known enzyme to achievechiral amines of high enantiomeric excess in laboratory scales. However, the low operational stabilityof Cv-ATA limits the enzyme applicability on larger scales. In order to improve the operational stabilityof Cv-ATA, and thereby extending its applicability, factors (additives, co-solvents, organic solvents anddifferent temperatures) targeting enzyme stability and activity were explored in order to find out how tostore and apply the enzyme. The present investigation shows that the melting point of Cv-ATA is improvedby adding sucrose or glycerol, separately. Further, by storing the enzyme at higher concentrations and inco-solvents, such as; 50% glycerol, 20% methanol or 10% DMSO, the active dimeric structure of Cv-ATAis retained. Enzyme stored in 50% glycerol at −20◦C was e.g., still fully active after 6 months. Finally,the enzyme performance was improved 5-fold by a co-lyophilization with surfactants prior to usage inisooctane.

  • 44. Córdova, Armando
    et al.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Anderson, Mattias
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Afewerki, Samson
    Efficient Synthesis Of Amines And Amides From Alcohols And Aldehydes By Using Cascade Catalysis2015Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    The present invention relates generally to an eco-friendly methodology for the conversion of alcohols and aldehydes to amines and amides using an integrated enzyme cascade system with metal-and organocatalysis. More specifically, the present invention relates to synthesis of capsaicinoids starting from vanillin alcohol and using a combination of an enzyme cascade system and catalysts. Furthermore, the method also relates to synthesis of capsaicinoids derivatives starting from vanillin alcohol derivatives and using a combination of an enzyme cascade system and catalysts.

  • 45. DeSantis, G.
    et al.
    Berglund, P.
    University of Toronto, Canada.
    Stabile, M. R.
    Gold, M.
    Jones, J. B.
    Site-directed mutagenesis combined with chemical modification as a strategy for altering the specificity of the S1 and S1' pockets of subtilisin Bacillus lentus1998In: Biochemistry, ISSN 00062960 (ISSN), Vol. 37, no 17, p. 5968-5973Article in journal (Refereed)
    Abstract [en]

    By combining site-directed mutagenesis with chemical modification, we have altered the S1 and S1 pocket specificity of subtilisin Bacillus lentus (SBL) through the incorporation. of unnatural amino acid moieties, in the following manner: WT → Cys(mutant) + H3CSO2SR → Cys-SR, where R may be infinitely variable. A paradigm between extent of activity changes and surface exposure of the modified residue has emerged. Modification of M222C, a buffed residue in the S1' pocket of SBL, caused dramatic changes in k(cat)/K(M), of an up to 122-fold decrease, while modification of S166C, which is located at the bottom of the S1 pocket and is partially surface exposed, effected more modest activity changes. Introduction of a positive charge at S166C does not alter k(cat)/K(M), whereas the introduction of a negative charge results in lowered activity, possibly due to electrostatic interference with oxyanion stabilization. Activity is virtually unaltered upon modification of S156C, which is located toward the bottom of the S1 pocket and surface exposed and whose side chain is solvated. An unexpected structure-activity relationship was revealed for S166C-SR enzymes in that the pattern of activity changes observed with increasing steric size of R was not monotonic. Molecular modeling analysis was used to analyze this unprecedented structure-activity relationship and revealed that the position of the β- carbon of Cys166 modulates binding of the P1 residue of the AAPF product inhibitor.

  • 46. Edlund, H.
    et al.
    Berglund, P.
    Mid Sweden University.
    Jensen, M.
    Hedenström, E.
    Högberg, H. -E
    Resolution of 2-methylalkanoic acids. Enantioselective esterification with long chain alcohols catalysed by Candida rugosa lipase1996In: Acta Chemica Scandinavica, ISSN 0904213X (ISSN), Vol. 50, no 8, p. 666-671Article in journal (Refereed)
    Abstract [en]

    Candida rugosa lipase catalysed resolutions of 2-methylalkanoic acids run on a large scale often display decreased enantiomeric rations (E-values) and reaction rates compared with small-scale experiments. By continuous control of the water activity (addition of inorganic salt/hydrated salt mixtures) this can be avoided. The importance of the proper choice of alcohol as well as its concentration is demonstrated. (R)-2-Methyloctanoic acid (8.6g) and (S)-2-methyl-1-octanol (4.5 g), both in 99.6% ee were prepared from 20 g racemic 2-methyloctanoic acid. © Acta Chemica Scandinavica 1996.

  • 47.
    Engelmark Cassimjee, Karim
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Affinity Tag Purification Method and Immobilization of the Promiscuous Enzyme Alanine Racemase2006Conference paper (Refereed)
  • 48.
    Engelmark Cassimjee, Karim
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Affinity Tag Purification Method of the Promiscuous Enzyme Alanine Racemase2006In: Book of abstracts, 2006Conference paper (Other academic)
  • 49.
    Engelmark Cassimjee, Karim
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Immobilization Method for the Promiscuous Enzyme Alanine Racemase2007In: BIOTRANS Oviedo 2007 / [ed] Vicente Gotor, 2007Conference paper (Refereed)
  • 50.
    Engelmark Cassimjee, Karim
    et al.
    KTH, School of Biotechnology (BIO), Biochemistry.
    Branneby, Cecilia
    Abedi, Vahak
    Wells, Andrew
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry.
    Transaminations with isopropyl amine: equilibrium displacement with yeast alcohol dehydrogenase coupled to in situ cofactor regeneration2010In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 46, no 30, p. 5569-5571Article in journal (Refereed)
    Abstract [en]

    Enantiopure chiral amines synthesis using omega-transaminases is hindered by an unfavourable equilibrium, but when using isopropylamine as the amine donor the equilibrium can be completely displaced by using a specific dehydrogenase in situ for removal of formed acetone.

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