Prolidase from Xanthomonas maltophilia: purification and characterization of the enzyme.
Prolidase (iminodipeptidase, EC 3.4.13.9) was purified from an extract of Xanthomonas maltophilia, by ammonium sulfate fractionation and sequential chromatographies on DEAE-Toyopearl, Toyopearl HW65C, FPLC-Hiload Superdex 200 pg, and FPLC-Hitrap Q columns, which an activity recovery of 2.3%. The enzyme was the most active at pH 7.5 with Leu-Pro as substrate. It was stable between pH 6.0 and 8.5 for 60 min at 37 degrees C and retained half of activity after 60 min at 37 degrees C. The isoelectric point of the enzyme was 3.7. Its molecular weight was estimated to be 100,000 by gel filtration on FPLC-Hiload Superdex 200 and 51,000 by SDS-PAGE, suggesting that it is a dimer. It hydrolyzed dipeptides only if proline is located at the carboxyl terminal position. The enzyme was inhibited by PCMB and o-phenanthroline, and was activated by Mn2+.
School of Pharmaceutical Sciences, Nagasaki University, Japan.
K
K
Suga
T
T
Kabashima
K
K
Ito
D
D
Tsuru
H
H
Okamura
J
J
Kataoka
T
T
Yoshimoto
D002852:Chromatography, Ion Exchange; D004150:Dipeptidases / Q000037:antagonists & inhibitors / Q000302:isolation & purification* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D008670:Metals / Q000494:pharmacology; D013379:Substrate Specificity; D013696:Temperature; D014974:Xanthomonas / Q000201:enzymology*
D007202:Indicators and Reagents; D008670:Metals; D004150:Dipeptidases; C022449:proline dipeptidase