The renal lesions associated with intrauterine hæmorrhage and fœtal death in pregnant rats given progesterone and an experimental diet

Abstract

L-Arabinose-negative mutants of Escherichia coli B/r, ara-53 and ara-139, are deficient in the enzyme L-ribulose 5-phosphate 4-epimerase; ara-53, further analyzed, accumulates large quantities of L-ribulose 5-phosphate when in- cubated with L-arabinose. The mutant sites are closely linked to the left of the previously ordered L-arabinose mutant sites, and probably represent the structural gene for L-ribulose 5-phosphate 4- epimerase (gene D) in the L-arabinose operon. The inducible levels of L-arabinose isomerase and L-ribulose 5-phosphate 4-epimerase vary cor- respondingly as a result of mutation in the structural gene for L-ribulokinase (gene B), further substantiating the dual structural and regulatory function of this gene locus. Ara-53