Advanced functionalization of polyhydroxyalkanoate via the UV-initiated thiol-ene click reaction
- 602 Downloads
Polyhydroxyalkanoates (PHAs) incorporating vinyl-bearing 3-hydroxyalkanoates were prepared in 8.5–12.9 g L−1 yield. The molar ratios (0–16 mol%) of the vinyl-bearing 3-hydroxyalkanoate derivatives were controlled by the continuous feeding of undecylenate at various concentrations. Subsequently, the PHAs were functionalized by UV-initiated thiol-ene click reaction and chemical modification. 1H NMR spectra suggested that 3-mercaptopropionic acid and 2-aminoethanethiol were successfully introduced into the vinyl-bearing PHA. Subsequently, chemical modification using fluorescein or a fibronectin active fragment (GRGDS) was attempted. The former yielded a PHA derivative capable of emitting fluorescence under UV irradiation, which was useful for determining the miscibility of PHA in a composite film comprising poly-ʟ-lactic acid (PLLA) and PHA. In the latter case, PHA bearing GRGDS peptides exhibited cell adhesiveness, suggesting that its biocompatibility was improved upon peptide introduction. Taken together, the UV-initiated thiol-ene click reaction was demonstrated to be useful in PHA modification.
KeywordsPolyhydroxyalkanoate Medium-chain length Click chemistry Double bond Ene-thiol click reaction
We thank Mr. Eiji Yamada and Mr. Naoya Nakagawa of Hokkaido University for their technical support in NMR measurements.
Compliance with ethical standards
This work was supported by Grant-in-Aid for Scientific Research (No. 21310060 and 21760632) from the Ministry of Education, Culture, Sports, Science, and Technology, Japan.
Conflict of interest
The authors declare that they have no competing interests.
This article does not contain any studies with human participants or animals performed by any of the authors.
- Lageveen RG, Huisman GW, Preusting H, Ketelaar P, Eggink G, Witholt B (1988) Formation of polyesters by Pseudomonas oleovorans: effect of substrates on formation and composition of poly-(R)-3-hydroxyalkanoates and poly-(R)-3-hydroxyalkenoates. Appl Environ Microbiol 54:2924–2932PubMedPubMedCentralGoogle Scholar
- Lee HJ, Choi MH, Kim TU, Yoon SC (2001) Accumulation of polyhydroxyalkanoic acid containing large amounts of unsaturated monomers in Pseudomonas fluorescens BM07 utilizing saccharides and its inhibition by 2-bromooctanoic acid. Appl Environ Microbiol 67:4963–4974CrossRefPubMedPubMedCentralGoogle Scholar
- Nomura CT, Taguchi K, Taguchi S, Doi Y (2004) Coexpression of genetically engineered 3-ketoacyl-ACP synthase III (fabH) and polyhydroxyalkanoate synthase (phaC) genes leads to short-chain-length-medium-chain-length polyhydroxyalkanoate copolymer production from glucose in Escherichia coli JM109. Appl Environ Microbiol 70:999–1007CrossRefPubMedPubMedCentralGoogle Scholar
- Tajima K, Han XR, Satoh Y, Satoh T, Ishii A, Araki Y, Munekata M, Taguchi S (2012) In vitro synthesis of polyhydroxyalkanoate (PHA) incorporating lactate (LA) with a block sequence by using a newly engineered thermostable PHA synthase from Pseudomonas sp. SG4502 with acquired LA-polymerizing activity. Appl Microbiol Biotechnol 94:365–376CrossRefPubMedGoogle Scholar