Substrate specificity of ribose-5-phosphate isomerases from Clostridium difficile and Thermotoga maritima.
The activity of ribose-5-phosphate isomerases (RpiB) from Clostridium difficile for D-ribose isomerization was optimal at pH 7.5 and 40 degrees C, while that from Thermotoga maritima for L-talose isomerization was optimal at pH 8.0 and 70 degrees C. C. difficile RpiB exhibited activity only with aldose substrates possessing hydroxyl groups oriented in the right-handed configuration (Fischer projections) at the C2 and C3 positions, such as D-ribose, D-allose, L-talose, L-lyxose, D-gulose, and L-mannose. In contrast, T. maritima RpiB displayed activity only with aldose substrates possessing hydroxyl groups configured the same direction at the C2, C3, and C4 positions, such as the D- and L-forms of ribose, talose, and allose.
Department of Bioscience and Biotechnology, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul, 143-701, South Korea.
Soo-Jin
SJ
Yeom
Bi-Na
BN
Kim
Chang-Su
CS
Park
Deok-Kun
DK
Oh
D019747:Aldose-Ketose Isomerases / Q000378:metabolism*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000378:metabolism*; D016360:Clostridioides difficile / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008969:Molecular Sequence Data; D015394:Molecular Structure; D016415:Sequence Alignment; D013379:Substrate Specificity; D013696:Temperature; D020124:Thermotoga maritima / Q000201:enzymology*
D001426:Bacterial Proteins; D019747:Aldose-Ketose Isomerases; C022548:ribosephosphate isomerase