Microbial reclamation of squid pen for the production of a novel extracellular serine protease by Lactobacillus paracasei subsp paracasei TKU012.
A protease-producing bacterium, strain TKU012, was isolated from infant vomited milk and identified as Lactobacillus paracasei subsp paracasei. Strain TKU012 produced protease when it was grown in a medium containing squid pen powder of marine waste. An extracellular protease was purified from culture supernatant by DEAE-Sepharose and Sephacryl S-100 chromatography. A protease, purified 77-fold to homogeneity in an overall yield of 11%, has a molecular weight of about 49 kDa estimated by SDS-PAGE. The protease was maximally active at pH 10 and 60 degrees C and showed substrate specificity to casein and gelatin. The protease retains 21% and 91% activity in the presence of Tween 20 (2% w/v) and SDS (2mM), respectively. The enzyme activity was reduced in the presence of PMSF and showed 23% sequence coverage rate with metalloprotease of Serratia marcescens. This is the first report of extracellular proteases purified from lactobacilli.
Wang
San-Lang
SL
Graduate Institute of Life Sciences, Tamkang University, Taipei 251, Taiwan. sabulo@mail.tku.edu.tw
Wang
Chun-Yuan
CY
Huang
Tsai-Yi
TY
D000818:Animals; D049832:Decapodiformes / Q000382:microbiology*; D004591:Electrophoresis, Polyacrylamide Gel; D005110:Extracellular Space / Q000201:enzymology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007223:Infant; D007778:Lactobacillus / Q000145:classification / Q000201:enzymology* / Q000254:growth & development / Q000302:isolation & purification; D008970:Molecular Weight; D010449:Peptide Mapping; D012685:Sepharose; D012697:Serine Endopeptidases / Q000096:biosynthesis*; D013379:Substrate Specificity; D013696:Temperature; D013997:Time Factors
D012685:Sepharose; D012697:Serine Endopeptidases