Cloning, Overexpression and Application of Lipase from Thermotolerant Bacillus subtilis TTP-06 in the Degradation of Polyhydroxyalkanoate

Indian J Microbiol. 2024 Sep;64(3):1290-1300. doi: 10.1007/s12088-024-01329-z. Epub 2024 Jun 20.

Abstract

Polyhydroxyalkanoates (PHAs) constitute a principal group of bio-degradable polymers that are produced by certain microbes under limited supply of nutrients. PHA is a linear polyester that comprises of 3-hydroxy fatty acid monomers. Triacylglycerol acylhydrolases are known to catalyze the hydrolysis of ester linkages and in turn they are beneficial in the degradation of PHA. In present study, lipase-catalyzed degradation of PHA synthesized by Priestia megatarium POD1 was monitored. A gene from thermotolerant Bacillus subtilis TTP-06 that was capable of expressing lipase enzyme was amplified by PCR, cloned into a pTZ57R/T-vector, transferred to an expression vector pET-23a (+) and expressed in Escherichia coli BL21 (DE3) cells. The recombinant enzyme purified to 19.37-fold had a molecular weight of 30 kDa (SDS-PAGE analysis). Scanning Electron Microscopy (SEM) revealed changes in the surface morphology of native and treated PHA films. Further, changes in molecular vibrations were confirmed by Fourier Transform Infrared Spectroscopy.

Supplementary information: The online version contains supplementary material available at 10.1007/s12088-024-01329-z.

Keywords: Biodegradation; FT-IR; Lipase; Polyhydroxyalkanoates (PHAs); SEM.