BioChem - DOS

Biosynthesis and Characterization of Polyhydroxyalkanoate Block Copolymer P3HB-b-P4HB

Biomacromolecules

Hu, Die; Chung, Ah-Leum; Wu, Lin-Ping; Zhang, Xin; Wu, Qiong; Chen, Jin-Chun; Chen, Guo-Qiang

<P>Polyhydroxyalkanoates (PHA) synthesis genes <I>phbC</I> and <I>orfZ</I> cloned from <named-content content-type='genus-species' xlink:type='simple'>Ralstonia eutropha</named-content> H16 were transformed into beta-oxidation weakened <named-content content-type='genus-species' xlink:type='simple'>Pseudomonas putida</named-content> KTOY08&Delta;<I>G</I>C, a mutant of <named-content content-type='genus-species' xlink:type='simple'>P. putida</named-content> KT2442. The recombinant <named-content content-type='genus-species' xlink:type='simple'>P. putida</named-content> strain termed KTHH06 was able to produce a short-chain-length PHA block copolymer consisting of poly(3-hydroxybutyrate) (P3HB) as one block and poly(4-hydroxybutyrate) (P4HB) as another block. One-dimensional and two-dimensional nuclear magnetic resonance (NMR) clearly indicated the polymer was a diblock copolymer consisting of 20 mol % P3HB as one block and 80 mol % P4HB as another one. Differential scanning calorimetric (DSC) showed that P3HB block melting temperatures (<I>T</I><SUB>m</SUB>) in the block copolymer P3HB-<I>b</I>-P4HB was shift to low temperature compared with homopolymer P3HB and a blend of P3HB and P4HB. The block copolymer with a number average molecular weight of 50000 Da and a polydispersity of 3.1 demonstrated a better yield and tensile strength compared with that of its related random copolymer and blend of homopolymers of P3HB and P4HB.</P><P><B>Graphic Abstract</B><BR><IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/bomaf6/2011/bomaf6.2011.12.issue-9/bm200660k/production/images/medium/bm-2011-00660k_0004.gif'></P>

2011

American Chemical Society

1525-7797

1526-4602

12

9

pp.3166-3173

10.1021/bm200660k

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART57448879