ACETYLORNITHINASE OF ESCHERICHIA COLI: PARTIAL PURIFICATION AND SOME PROPERTIES

Abstract

Compounds Used-N”l-Acetyl-n-ornithine was synthesized as previously described (5, 3).’ L-Ornithine monohydrochloride was obtained from the Mann Research Laboratories. Several of the acetylamino acids used, including acetyl-nn-methionine, were supplied by the California Foundation for Biochemical Research.2 Organisms-The organisms used are E. coli (ATCC 9637) and ornithinerequiring mutant 160-37 of E. coli (5, 1). Cultivation-The growth medium used is prepared at 50 X strength as follows. In distilled water (670 ml.) are dissolved, successively, MgSOr .7H20 (10.0 gm.), citric acid-H20 (100.0 gm.), K2HF04.anhydrous (500.0 gm.), and NaNH,HP04.4H20 (175.0 gm.), the final volume being about 1.00 liter.3 On 50-fold dilution with distilled water, the resulting single strength medium, designated E, has a pH of about 7.0; it is sterilized by autoclaving. Medium E is supplemented with dextrose (autoclaved sepa-