Properties and significance of an α-amylase produced by Myxococcus coralloides D |
| |
Authors: | M Esther Fárez-Vidal Antonia Fernández-Vivas F González JM Arias |
| |
Institution: | Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Granada, Spain |
| |
Abstract: | M.E.FÁREZ-VIDAL, A. FERNÁNDEZ-VIVAS, F. GONZÁLEZ AND J.M. ARIAS. 1995. The extracellular amylase activity from Myxococcus coralloides D was purified by Sephacryl S-200 gel filtration and by ion-exchange chromatography on DEAE-Sephadex A-25. The molecular weight was estimated by SDS-PAGE and by gel filtration as 22.5 kDa. The optimum temperature was 45°C. The pH range of high activity was between 6.5 and 8.5, with an optimum at pH 8.0. Activity was strongly inhibited by Hg2+, Zn2+, Cu2+, Ag+, Pb2+, Fe2+ and Fe3+, EDTA and glutardialdehyde, but was less affected by Ni2+ and Cd2+. Li+, Mg2+, Ba2+, Ca2+, N -ethylmaleimide, carbodiimide and phenyl methyl sulphonyl fluoride had almost no affect. The K m (45°C, pH 8) for starch hydrolysis was 2.0 times 10-3 gl-1. Comparison of the blue value-reducing curves with the time of appearance of maltose identified the enzyme produced by M. coralloides D as an α-amylase. |
| |
Keywords: | |
|
|