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Research Support, Non-U.S. Gov't
- The Influence of NaCl and Carbonylcyanide-m-Chlorophenylhydrazone on the Production of Extracellular Proteases in a Marine Vibrio Strain
- Young Jae Kim
- J. Microbiol. 2004;42(2):156-159.
- DOI: https://doi.org/2028 [pii]
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Abstract
- In general, the salinity of the ocean is close to 3.5% and marine vibrios possess the respiratory chainlinked Na+ pump. The influence of sodium chloride and the proton conductor carbonylcyanide m-chlorophenylhydrazone (CCCP) on the production of extracellular proteases in a marine Vibrio strain was examined. At the concentration of 0.5 M, sodium chloride minimally inhibited the activity of extracellular proteases by approximately 16%, whereas at the same concentration, the producton of extracellular proteases was severely inhibited. On the other hand, the production of extracellular proteases was completely inhibited by the addition of 2 μM CCCP at pH 8.5, where the respiratory chain-linked Na^+ pump functions.
- Purification and Characterization of an Extracellular Protease from Culture Filtrate of Salmonella schttmulleri
- Na, Byoung Kuk , Song, Chul Yong
- J. Microbiol. 1995;33(3):244-251.
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Abstract
- An extracellular protease of Salmonella schottmulleri was purified from culture filtrate by using 0-75% ammonium sulfate precipitation, DEAE Sepharose Fast Flow ion exchange chromatography, Ultrogel HA chromatography and Sephacryl S-200 HR molecular sieve chromatography. To measure enzyme activity, synthetic dipeptide substrate (CBZ-arg-arg-AFC) with low molecular weight was employed as substrate. The molecular weight of the purified enzyme was approximately 80 kDa when determined by gel filtration on Sephacryl S-200 HR and 73 kDa when estimated by SDS-PAGE. The isoelectric point was 5.45. The activity of the purified enzyme was inhibited by metal chelating agesnts such as EDTA and 1.10-phenanthroline. The divalent cations, such as Ca^2+, Zn^2+, Fe^2+, Mg^2+ enhanced its activity. These results suggested that it was a metalloprotease. It had a narrow pH optimum of 6.5-7.5 with a maximum at pH 7.0 and a temperature optimum of 40℃. It was stable at least for 1 week at 40℃ and maintained its activity for 24 hours at 50℃, but it was rapidly inactivated at 65℃. This protease was shown to be sensitive to sodium 50℃, but it was rapidly inactivated at 65℃. This protease was shown to be sensitive to sodium 50℃, but it was rapidly inactivated at 65℃. This protease was shown to be sensitive to sodium 50℃, but it was rapidly inactivated at 65℃. This protease was shown to be sensitive to sodium dodecyl sulfate (SDS) and was inactivated in a dose-dependent manner. However, it was resistant to Triton X-100 and the activity was enhanced to 32.3% with treatment of 0.025% Triton X-100.
- Characterization of Bacillus cereus SH-7 Extracellular Protease
- Hak Kyu Yi , Young Jin Chum , Han Bok Kim
- J. Microbiol. 1999;37(4):213-217.
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Abstract
- An extracellular endopeptidase from Bacillus cereus SH-7 was purified to homogeneity. The protease was most active at pH 8 and 40 C, respectively. The molecular mass of the protease was 40 kDa on SDS-PAGE, and 120 kDa by gel filtration, suggesting that the native enzyme is composed of three homogeneous subunits. The K_m and V_max values of the protease for N-succinyl-(Ala)_2-Pro-Phe-p-nitroanilide were 11.11 mM and 170 nmol/mg of protein/min, respectively. The protease was also identified as a metalloprotease. The bioactivity of the SH-7 protease will need further study in the future.
- Purification and Characterization of Two Extracellular Proteases from Oligotropha carboxydovorans DSM 1227
- Kang, Beom Sik , Jeon, Sang Jun , Kim, Min Young
- J. Microbiol. 1999;37(1):14-20.
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Abstract
- Two extracellular proteases, EP I and EP II, from cells of Oligotropha carboxydovorans (formerly Pseudomonas carboxydovorans) DSM 1227 grown in nutrient broth were purified to greater than 95% homogeneity in five steps using azocasein as a substrate. The final specific activities of EPs I and II were 214.9 and 667.4 units per mg of protein. The molecular weights of native EPs I and II were determined to be 23,000. Sodium dodecyl sulfate-gel electrophoresis revealed the two enzymes to be monomers. The enzymes were found to be serine-type proteases. The activity of EP I was stimulated by Ca^2+, Mg^2+, and Ba^2+, but that of EP II was not. The enzymes were completely inhibited by Fe^2+, Hg^2+, Co^2+, Zn^2+, and Cd^2+. EDTA and EGTA exhibited a strong inhibitory effect on EP I. The optimal pH for the two enzymes was pH 9.0. The optimal temperatures for EP I and II were 60 and 50℃, respectively. The enzymes were stable under alkaline conditions. The thermal stability of EP I was higher than that of EP II. Cell-free extracts did not inhibit the purified enzymes. The enzymes were active on casein, azocasein, azocoll, and carbon monoxide dehydrogenase, but weakly active with bovine serum albumin.
- Purification and Characterization of Extracellular Temperature-Stable Serine Protease from Aeromonas hydrophila
- Soo-Jin Cho , Jong-Ho Park , Seong Joo Park , Jong-Soon Lim , Eung Ho Kim , Yeon-Jae Cho , Kwang-Soo Shin
- J. Microbiol. 2003;41(3):207-211.
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Abstract
- Extracellular protease, from Aeromonas hydrophila Ni 39, was purified 16.7-fold to electrophoretic homogeneity with an overall yield of 19.9%, through a purification procedure of acetone precipitation, and Q Sepharose and Sephacryl S-200 chromatographies. The isoelectric point of the enzyme was 6.0 and the molecular mass, as determined by Sephacryl S-200 HR chromatography, was found to be about 102 kDa. SDS/PAGE revealed that the enzyme consisted of two subunits, with molecular masses of 65.9 kDa. Under standard assay conditions, the apparent K_m value of the enzyme toward casein was 0.32 mg/ml. About 90% of the proteolytic activity remained after heating at 60 ℃ for 30 min. The highest rate of azocasein hydrolysis for the enzyme was reached at 60℃, and the optimum pH of the enzyme was 9.0. The enzyme was inhibited by the serine protease inhibitor, phenylmethylsulfonyl fluoride (PMSF), by about 87.9%, but not by E64, EDTA, pepstatin or 1,10-phenanthroline. The enzyme activity was inhibited slightly by Ca_2^+, Mg_2^+ and Zn_2^+ ions.
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