Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

5-Oxyoprolinase: Structure and mechanism of action

Thesis/Dissertation ·
OSTI ID:6277769
5-Oxoprolinase catalyzes the endergonic cleavage of 5-oxo-L-proline to L-glutamate, coupled to the exergonic hydrolysis of ATP to ADP and P{sub i}. In the present studies, the enzyme present in a strain of Pseudomonas putida was found to be composed of two protein components. Component A catalyzes 5-oxo-L-proline-dependent cleavage of ATP without 5-oxyoproline decyclization. Component B is required to couple ATP hydrolysis to the ring-opening of 5-oxoproline. The two components have been purified to apparent homogeneity. When the 5-oxoprolinase reactions were carried out to 90% completion in H{sub 2} {sup 18}O, the residual 5-oxoproline contained {sup 18}O in the amide carbonyl group. Glutamate and P{sub i} isolated from the complete reactions conducted in H{sub 2}{sup 18}O were mono- and di-labeled with the isotope. No isotope was incorporated into 5-oxoproline if Component A was used alone. Studies with 5-oxoproline analogs showed that dilabeling of P{sub i} occurred only in coupled or partially coupled reactions. Using 5-({sup 18}O)oxo-L-(5-{sup 13}C)proline, the reactions were further analyzed by {sup 13}C-NMR. 5-Oxoprolinase from rat kidney was used as a comparison in all mechanistic studies, and similar results were obtained. These findings are consistent with the view that the reaction involves enzyme-bound, phosphorylated intermediates, and provided strong evidence for a phosphorylated tetrahedral intermediate, the formation of which is required for the coupling.
Research Organization:
Cornell Univ., Ithaca, NY (USA)
OSTI ID:
6277769
Country of Publication:
United States
Language:
English

Similar Records

/sup 18/O-studies on the mechanism of action of 5-oxoprolinase
Conference · Thu May 01 00:00:00 EDT 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) · OSTI ID:5283007
Evidence that a phosphorylated derivative of 5-oxoproline (5-OP) is an intermediate in the reaction catalyzed by 5-oxoprolinase
Conference · Thu May 01 00:00:00 EDT 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) · OSTI ID:5272254
Evidence for lens oxoprolinase, an enzyme of the gamma-glutamyl cycle. [Rabbits]
Journal Article · Sat Mar 01 00:00:00 EDT 1975 · Invest. Ophthalmol.; (United States) · OSTI ID:7199288

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINES
AMINO ACIDS
ATP
AZOLES
BACTERIA
BIOCHEMICAL REACTION KINETICS
CARBON 13
CARBON ISOTOPES
CARBOXYLIC ACIDS
ENZYMES
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
FRACTIONATION
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYDROLASES
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LIGHT NUCLEI
METABOLISM
MICROORGANISMS
MOLECULAR STRUCTURE
NMR SPECTRA
NUCLEI
NUCLEOTIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXYGEN 18
OXYGEN ISOTOPES
PROLINE
PSEUDOMONAS
PYRROLES
PYRROLIDINES
REACTION KINETICS
SEPARATION PROCESSES
SPECTRA
STABLE ISOTOPES
TRACER TECHNIQUES