Abstract

An esterase gene (estC) was isolated from a genomic library of Lactobacillus casei LILA. The estC gene consisted of a 777 bp open reading frame encoding a putative peptide of 28.9 kDa. A recombinant EstC fusion protein containing a C-terminal six-histidine tag was constructed and purified to electrophoretic homogeneity. Characterization of EstC revealed that it was a serine-dependent dimeric enzyme. Optimum temperature, NaCl concentration, and pH for EstC were determined to be 30°C, 0% NaCl, and pH 5.5, respectively. EstC had significant activity under conditions simulating those of ripening cheese (10°C, 4% NaCl, and pH 5.1). Kinetic constants (KM and Vmax) were determined for EstC action on a variety of ethyl esters and ester compounds consisting of substituted phenyl alcohols and short n-chain fatty acids. For comparison purposes, the previously studied EstA from Lactococcus lactis MG1363 was purified to electrophoretic homogeneity and its substrate selectivity determined in a similar fashion. Different substrate selectivities were observed for EstC and EstA.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.