Scientific Reports of the Faculty of Agriculture, Okayama University
Published by the Faculty of Agriculture, Okayama University
ONLINE ISSN : 2186-7755

Alanine Racemase from an Acidophilic Bacterium, Acidiphilium organovorum

Seow, Teck Keong
Inagaki, Kenji Kaken ID researchmap
Tanaka, Hidehiko
Abstract
Alanine racemase(EC 5.1.1.1)was screened from several acidophilic bacteria.Acidiphilium organovorum 13H showed the highest activity and was chosen as the representative source to study alaine racemase from acidphlic bacteria.The enzyme was found to be localised in the cytoplasm of the bacteria.Relative molecular mass syudies indicated that it had a dimeric native structure with identical subunits of about 34 kDa each.Maximum activity was observed between 50 and 60℃and at pH9.There was no loss of enzyme activity even after incubation at 65℃.The loss of activity upon dialysis against pyridoxal 5'-phosphate-free buffer containing hydroxylamine,and its partial recovery upon subsequent dialysis against buffer containing phyridoxal 5'-phosphate suggested that the enzyme required piridoxal 5'-phosphate as a co-factor for its catalytic activity.
Keywords
Alanine racemase
Acidophile
Acidiphilium organovorum
Phyridoxal 5'-phosphate
ISSN
0474-0254
NCID
AN00033029