𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Alternate putrescine metabolites: Quantitative analysis of Δ′-pyrroline oxidation to 2-pyrrolidone in tissue homogenates by high-pressure liquid chromatography

✍ Scribed by David W. Lundgren; Holly Tevesz; Elisa A. Krill


Book ID
102988346
Publisher
Elsevier Science
Year
1985
Tongue
English
Weight
846 KB
Volume
148
Category
Article
ISSN
0003-2697

No coin nor oath required. For personal study only.

✦ Synopsis


A sensitive analytical procedure for following the oxidation of A'-pyrroline to 2-pyrrolidone in tissue homogenates is described. Homogenates are extracted with chloroform/acetonitrile and fractionated by high-performance liquid chromatography, and 2-pyrrolidone is quantitated by monitoring the column effluent at 200 nm. The lower limit of 2-pyrrolidone that can be accurately (+5%) quantitated is approximately 100 pmol. Phenazine methosulfate significantly enhances the rate of 2-pyrrolidone biosynthesis from A'-pyrroline. Phenazine methosulfate and reduced gfutathione are required to obtain proportionality between 2-pyrrolidone formation and incubation time. Formation of 2-pyrrolidone as a function of protein concentration is linear and 2-pyrrolidone biosynthesis as a function of A'-pyrroline concentration is characterized by hyperbolic kinetics. Based on analysis of enzyme activity in different tissues, liver appears to play the dominant role in 2-pyrrolidone biosynthesis. The metabolic step from A'-pyrroline to 2-pyrrolidone was localized in the cellular cytosol. These results demonstrate that the oxidation of A'-pyrroline to 2-pyrrolidone is enzyme mediated and provide a useful method for further characterization of this metabolic step. o 1985 Academic PI~SS, h.