Production, purification, and characterization of a novel thermostable serine protease from soil isolate, Streptomyces tendae.
An isolate of Streptomyces tendae produced a extracellular protease which was purified to apparent homogeneity giving a single band on SDS-PAGE with a molecular mass of 21 kDa. Optimum activity was at 70 degrees C and pH 6. It was stable at 55 degrees C for 30 min and between pH 4 and 9. It was resistant to neutral detergents and organic solvents such as Triton X-100, Tween 80, methanol, ethanol, acetone, and 2-propanol at 5% (v/v). The enzyme was completely inhibited by 5 mM PMSF, indicating it to be a serine protease. N-terminal amino acid sequence did not show any homology with other known proteolytic enzymes. The protease may therefore be a novel neutral serine protease, which is stable at high temperature and over a broad range of pH.
Seong
Chi-Nam
CN
Department of Biological Science, Sunchon National University, Jeonnam 540-742, Korea.
Jo
Jung-Sun
JS
Choi
Sang-Ki
SK
Kim
Si-Wouk
SW
Kim
Sung-Jun
SJ
Lee
Oh-Hyung
OH
Han
Ji-Man
JM
Yoo
Jin-Cheol
JC
D000595:Amino Acid Sequence; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000737:chemistry; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000737:chemistry; D008969:Molecular Sequence Data; D008970:Molecular Weight; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000096:biosynthesis* / Q000737:chemistry* / Q000302:isolation & purification; D013045:Species Specificity; D013302:Streptomyces / Q000145:classification* / Q000201:enzymology*; D013696:Temperature
D004791:Enzyme Inhibitors; D008670:Metals; D012697:Serine Endopeptidases