| Autor: |
van Alebeek, G.-J. W. M., Kreuwels, M. J. J., Keltjens, J. T., Vogels, G. D. |
| Zdroj: |
Archives of Microbiology; June 1994, Vol. 161 Issue: 6 p514-520, 7p |
| Abstrakt: |
Cyclic 2,3-diphosphoglycerate (cDPG) hydrolase activity was demonstrated in cofactor-free extract of Methanobacterium thermoautotrophicum (strain ?H), but not in crude extract. Only after ultrafiltration or dialysis of curde extract cDPG hydrolase activity could be shown. cDPG hydrolysis was optimal at pH 6.0 and 60?°C. Hydrolysis of cDPG occurred under nitrogen or hydrogen atmosphere and was completely inhibited by oxygen. Phosphate and potassium chloride were also strong inhibitors: 50% inhibition occurred at 0.6?–?0.7 m M phosphate or 0.2 M KCl. The enzyme was localized in the membrane fraction and could be solubilized for approximately 60% by treatment with 25 m M of the detergent CHAPS. The K m and the V max for cDPG were determined at 60?°C and were 59 m M and 216 mU/mg, respectively. Furthermore, cDPG hydrolase was dependent on the presence of Co 2+. The role of cDPG and cDPG hydrolase is discussed. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
Full text from SpringerLink