| Title | InhA-Like Protease Secreted by Bacillus sp. S17110 Inhabited in Turban Shell |
|---|---|
| Author | Sang Chul Jung1, Hyoung-Rok Paik1, Mi Sun Kim1, Keun Sik Baik1, Woo-Yiel Lee2, Chi Nam Seong1, and Sang Ki Choi1* |
| Address | 1Department of Biological Sciences, College of Natural Science, Sunchon National University, Jeonnam 540-742, Republic of Korea, 2Department of Pharmaceutical Engineering, Konyang University, Nonsan 320-711, Republic of Korea |
| Bibliography | Journal of Microbiology, 45(5),402-408, 2007, |
| DOI | |
| Key Words | protease, turban shell, immune inhibitor, Bacillus |
| Abstract | A strain producing a potent protease was isolated from turban shell. The strain was identified as Bacillus sp. S17110 based on phylogenetic analysis. The enzyme was purified from culture supernatant of Bacillus sp. S17110 to homogeneity by ammonium sulfate precipitation, SP-Sepharose, and DEAE-Sepharose anion exchange chromatography. Protease activity of the purified protein against casein was found to be stable at pH 7 to pH 10 and around 50°C. Approximately 70% of proteolytic activity of the enzyme was detected either in the presence of 100 mM SDS or Tween 20. The enzyme activity was enhanced in the presence of Ca2+, Zn2+, Mg2+, but was inhibited by EDTA, indicating that it requires metal for its activity. The purified enzyme was found to be a monomeric protein with a molecular mass of 75 kDa, as estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and gel filtration chromatography. The purified enzyme was analyzed through peptide fingerprint mass spectra generated from matrix-assisted laser desorption ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS) and a BLAST search, and identified as immune inhibitor A (inhA) deduced from nucleotide sequence of B. cereus G9241. Since InhA was identified as protease that cleave antibacterial proteins found in insect, inhA-like protease purified from Bacillus sp. S17110 might be pathogenic to sea invertebrates. |
| Download PDF | 45(5)_05.pdf |