Polyhydroxyalkanoates synthases

Polyhydroxyalkanoate synthase (systematic name acyl-CoA 3-hydroxybutyrate 0-acyltransferase EC 2.3.1. class) is responsible for the polymerizations of PHAs in vivo because it catalyzes the stereoselective conversion of (/ )-3-hydroxyacyl-CoA substrates to PHAs with the concomitant release of CoA (see Fig. 2) [3]. 

Solaiman, D. K. Y., Ashby, R. D., and Foglia, T. A. 2000. Rapid and specific identification of medium-chain-length polyhydroxyalkanoate synthase gene by polymerase chain reaction. Appl. Microbiol. Biotechnol., 53, 690-694. 

Solaiman, D. K. Y. 2002. Polymerase-chain-reaction-based detection of individual polyhydroxyalkanoate synthase phaCl and phaC2 genes. Biotechnol. Lett., 24, 245-250. 

Peters, V., Becher, D., and Rehm, B.H.A. (2007) The inherent property of polyhydroxyalkanoate synthase to form spherical PHA granules at the cell poles the core region is required for polar localization. J. Biotechnol., 132, 238-245. 

Gerngross, T.U., Snell, K.D., Peoples, O.P., Sinskey, A.J., Csuhai, E., Masamune, S., and Stubbe, J. (1994) Overexpression and purification of the soluble polyhydroxyalkanoate synthase from Alcaligenes eutrophus evidence for a required posttranslational modification for catalytic activity. Biochemistry, 33, 9311-9320. 

Qi, Q., Steinbtichel, A., and Rehm, B.H.A. (2000) In vitro synthesis of poly(3 -hydroxydecanoate) purification of type II polyhydroxyalkanoate synthases PhaCl and PhaC2 from Pseudomonas aeruginosa and development of an enzyme assay. Appl. Microbiol. Biotechnol., 54, 37-43. 

Park S, Yang T, Kang H, Lee S, Lee E, Kim T (2008a) New polyhydroxyalkanoate synthase mutant, useful for preparing lactate polymer or lactate copolymer. W02008062999-A1 KR2008047279-A... 

Sheu D-S, Lee C-Y (2004) Altering the substrate specificity of polyhydroxyalkanoate synthase 1 derived from Pseudomonas putida GPol by localized semirandom mutagenesis. J Bacteriol 186 4177-4184... 

Yuan W, Jia Y, Han J, SneU K, Miih U, Sinskey A et til (2001) Class I and III polyhydroxyalkanoate synthases from Ralstonia eutropha and Allochrorruitium vinosum characterization and substrate specifidty studies. Arc Biochem Biophys 394 87-98 Yusoff S (2006) Renewable eneigy from palm oil—Innovation on effective utilization of waste. J Cleaner Prod 14 87-93... 

Polyhydroxyalkanoate synthases can use many different substrates and the number of viable pathways for the biosynthesis of PHAs is huge. When new substrates are used, novel PHAs can be produced. In aiming to reduce production costs, it will be useful to search for bacteria that can synthesize precursor substrates from simple and cheap carbon sources [36,92]. It has also been revealed that, when a PHA synthase enzyme is expressed in a different host microbe, it may result in different substrate speciflcity and therefore new PHAs with new chemical and physical properties are accessible [11]. 

Yilmaz M, Soran H, Beyatli Y (2005) Determination of poly-P-hydroxybutyrate (PHB) production by some Bacillus spp. World J Microbiol Biotechnol 21 565-566 Zhao HY, Li HM, Qin LF, Wang HH, Chen G-Q (2007) Disruption of the polyhydroxyalkanoate synthase gene in Aeromonas hydrophila reduces its survival ability under stress conditions. FEMS Microbiol Lett 276 34-41... 

Chen JY, Liu T, Zheng Z, Chen JC, Chen GQ (2004) Polyhydroxyalkanoate synthases PhaCl and PhaC2 from Pseudomonas stutzeri 1317 had different substrate specificities. FEMS Microbiol Lett 234 231-237... 

Stubbe J, Tian J, He A, Sinskey AJ, Lawrence AG, liu P (2005) Nontemplate-dependent polymerization processes polyhydroxyalkanoate synthases as a paradigm. Annu Rev Biochem 74 433-480... 

Taguchi K, Aoyagi Y, Matsusaki H, Fukui T, Doi Y (2(X)3) Co-expression of 3-ketoacyl-ACP reductase and polyhydroxyalkanoate synthase genes induces PHA production in Escherichia coli HBlOl strain. FEMS Microbiol Lett 176 183-190 Tajima K, Igari T, Nishimura D, Nakamura M, Satoh Y, Munekata M (2003) Isolation and characterization of Bacillus sp. INT005 accumulating polyhydroxyalkanoate (PHA) from gas field soil. J Biosci Bioeng 95 77-81... 

Hinz, H.J., and Steinbiichel, A. (2001) Matrix-assisted in vitro refolding of Pseudomonas aeruginosa class II polyhydroxyalkanoate synthase from inclusion bodies produced in recombinant Escherichia coli. Biochem. J., 358, 263-268. 

Amara, A.A. and Rehm, B.H.A. (2003) Replacement of the catalytic nucleophile cysteine-296 by serine in class II polyhydroxyalkanoate synthase from Pseudomonas aeruginosa-mediated synthesis of a new polyester identification of catalytic residues. Biochem. J., 374, 413-421. 

The first biosynthetic system for LA-based polyesters was created in recombinant E. coli (Taguchi et al., 2008). A coenzyme A (CoA) transferase gene and the engineered polyhydroxyalkanoate synthase gene were introduced into E. coli, and the one-step biosynthesis of the LA-incorporated copolyester, P(6 mol% LA-co-94 mol% 3HB), with a number-average molecular weight of 1.9 x 10, was successfully demonstrated. To date, the E. coli platform has been used to produce various LA-based polymers incorporating 3-hydroxybutyrate (3HB), 3-hydroxyvalerate, 3-hydroxyhexanoate, and 2-hydroxy acids(Shozui et al., 2009 Yamada et al., 2009 Han et al., 2011 Matsumoto et al., 2011). 

Matsumoto K, Ishiyama A, Sakai K, Shiba T, Taguchi S (2011) Biosynthesis of glycolate-based polyesters containing medium chain-length 3-hydroxyalkanoates in recombinant Escherichia coli expressing engineered polyhydroxyalkanoate synthase. J Biotechnol, 156, 214-217. 

Table 8.1 Classification of polyhydroxyalkanoate synthases based on their subunit composition and substrate specificity (Rehm, 2003)...

Lu XY, Zhang WJ, Wu Q, Chen GQ (2005) Molecular cloning and functional analysis of two polyhydroxyalkanoate synthases from two strains of Aeromonas hydrophila spp. FEMS Microbiol Lett 243 149-155... 

Zhao YH, Qin LF, Wang HT, Chen GQ (2007) Deletion of polyhydroxyalkanoate synthase gene in Aeromonas hydrophila reduces its survival ability under stress conditions. FEMS Microbiol Lett 276 34—41... 

Figure 7.7 Common metabolic pathways that are involved in the biosynthesis of PHA in microorganisms. FabC malonyl-CoA acyl carrier protein (ACP) transcylase, FabD malonyl-CoA-ACP transacylase, FabG 3-ketoacyl-CoA reductase, PhaA P-ketothiolase, PhaB NAOH-dependent acetoacetyl-CoA reductase, PhaC polyhydroxyalkanoates synthase, PhaG 3-hydroxyacyl-ACP GoA transferase, PhaJ (R)-enoyl-GoA hydratase and TCA tricarboxylic acid...

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