Clostridium sticklandii proline reductase

D-proline reductase Anaerobic respiration Clostridium sticklandii 104, 105... 

Clostridium sticklandii also expresses a proline reductase that can reduc-tively cleave proline to 8-aminovalerate (Seto and Stadtman 1976). PR was first purified by Seto and Stadtman (1976) by following the decomposition of proUne in the presence of dithiothreitol or NADH. They found PR to have a denatured mass of approximately 30kDa (sodium dodecyl sulfate-polyacrylomide gel electrophoresis SDS-PAGE) and a native size of approximately 300 kDa. The addition of selenite to the growth medium of C sticklandii did increase the specific activity of PR in extracts by threefold however, no selenium was detected in the purified enzyme. It should be noted that this purified enzyme had lost the ability to couple reduction of proline to NADH and thus probably was missing one or more components of the complete enzyme complex. 

Seto B. 1980. Chemical characterization of an alkali-labile bond in the polypeptide of proline reductase from Clostridium sticklandii. J Biol Chem 255 5004-6. 

Stadtman TC, Elliott P. 1957. Studies on the Enzymatic Reduction of amino acids II. Purification and properties of ao-proline reductase and a prohne racemase from Clostridium sticklandii. 1 Biol Chem 228 983-97. 

Other pyruvate-containing enzymes include aspartate /3-decarboxylase from Escherichia coli, the enzyme that cattdyzes the formation of /3-alanine for the synthesis of pantothenic acid (Section 12.2.4) proline reductase from Clostridium sticklandii phosphatidylserine decarboxylase from E. coli and phenyltdtuiine tuninoticmsferase from Pseudomonas fluorescens. Phospho-pemtetheinoyl cysteine deceu boxylase, involved in the synthesis of coenzyme A (Section 12.2.1), and S-adenosylmethionine decarboxylase seem to be the only mammtditm pyruvoyl enzymes (SneU, 1990). 

Proline racemase occurs in Clostridium sticklandii, which produces 8-aminovalerate from L-proline. Proline racemase and D-proline reductase are responsible for the conversion L-proline is racemized by proline racemase to form D-proline, which is converted into 5-aminovalerate by D-proline reductase (E.C. 1.4.4.1). 

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