• Journal of Microbiology and Biotechnology
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• v.28 no.3
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• pp.448-453
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• 2018

In this study, a 107 kDa protease from psychrophilic Janthinobacterium lividum PAMC 26541 was purified by anion-exchange chromatography. The specific activity of the purified protease was 264 U/mg, and the overall yield was 12.5%. The J. lividum PAMC 25641 protease showed optimal activity at pH 7.0-7.5 and $40^{\circ}C$. Protease activity was inhibited by PMSF, but not by DTT. On the basis of the N-terminal sequence of the purified protease, the gene encoding the cold-adapted protease from J. lividum PAMC 25641 was cloned into the pET-28a(+) vector and heterologously expressed in Escherichia coli BL21(DE3) as an intracellular soluble protein.

• Journal of Microbiology
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• v.39 no.2
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• pp.139-141
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• 2001

Medium-chain length polyhydrexyalkanoic acids (MCL-PHAs) degrading bacterium was isolated from the soil. The bacterium was identified as Janthinobacterium lividum by its biochemical properties, cell membrane fatty acids composition, and 16S rDNA sequence analysis. The bacterium showed a similarity of 0.911 with J. lividum according to the cell membrane fatty acids analysis and a similarity of 97% in the 16S rDNA requence analysis. Culture supernatant of the bacterium skewed the highest depolymerase activity toward polyhydroxynonanoic acid (PHN) that did not degrade the poly-$\beta$-hydroxybutyric acid (PHB). The esterase activity was also detected with p-nitrophenyl (PNP) esters of fatty acids such as PNP-dodecanoic PNP-dodecanoic acid, PNP-decanoic acid, and PNP-hexanoic acid.