Construction of recombinant Bacillus subtilis for production of polyhydroxyalkanoates

State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Shenzhen, China.
Applied Biochemistry and Biotechnology (Impact Factor: 1.74). 02/2006; 129-132(1):1015-22. DOI: 10.1385/ABAB:132:1:1015
Source: PubMed


Polyhydroxyalkanoates (PHAs) are polyesters of hydroxyalkanoates synthesized by numerous bacteria as intracellular carbon and energy storage compounds and accumulated as granules in the cytoplasm of cells. In this work, we constructed two recombinant plasmids, pBE2C1 and pBE2C1AB, containing one or two PHA synthse genes, respectively. The two plasmids were inserted into Bacillus subtilis DB104 to generate modified strains, B. subtilis/pBE2C1 and B. subtilis/pBE2C1AB. The two recombinants strains were subjected to fermentation and showed PHA accumulation, the first reported example of mcl-PHA production in B. subtilis. Gas Chromatography analysis identified the compound produced by B. subtilis/pBE2C1 to be a hydroxydecanoate-co-hydroxydodecanoate (HD-co-HDD) polymer whereas that produced by B. subtilis/pBE2C1AB was a hydroxybutyrate-co-hydroxydecanoate-co-hydroxydodecanoate (HB-HD-HDD) polymer.

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    • "One of the recombinant E . coli that produce high yield of P ( 3HB ) content is the E . coli JM109 transformant harbouring phaC Cs ( Bhubalan et al . , 2011a ) . The synthase was from Chromobacterium sp USM2 . P . aeruginosa phaC1AB and phaC1 from R . eutropha were used as additional synthase to B . subtilis DB104 ( Wang et al . , 2006 ) . The production of MCL - PHAs was found and the recombinant strain was the first of B . subtilis to show the production of PHA using the synthase from different PHA producers ."
    06/2014, Degree: Bachelor of Applied Science of Conservation and Management of Biodiversity, Supervisor: Dr. Kesaven Bhubalan
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    • "We investigate the metabolic networks of three model organisms, namely Bacillus subtilis (Oh et al., 2007), Escherichia coli (Feist et al., 2007), and seeds of Hordeum vulgare (Grafahrend-Belau et al., 2009), for which growth was predicted in silico and experimentally validated. All considered organisms have several important agricultural or biotechnological applications: B. subtilis is used for food and enzyme production and has been genetically engineered for producing riboflavin and polyhydroxyalkanoates (Schallmey et al., 2004; Perkins et al., 1999; Wang et al., 2006); E. coli has a long history of biotechnological applications, such as: production of insulin, lycopene, and succinic acid (Goeddel et al., 1979; Alper et al., 2005; Lee et al., 2005), and is currently explored for its use in producing polymers and biofuels (Atsumi et al., 2008; Bond-Watts et al., 2011; Yim et al., 2011); H. vulgare has been genetically engineered for enhanced breeding properties, protein synthesis, food and cellulose production (Horvath et al., 2000, 2001; von Wettstein et al., 2000; Patel et al., 2000). We point out that our approach is not restricted to optimizing biomass yield, and thus allows for the detection of reactions which, when introduced into the respective network, improve any metabolic objective of interest. "
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