Cloning and properties of the Salmonella typhimurium tricarboxylate transport operon in Escherichia coli

Journal Article · Mon Feb 01 00:00:00 EST 1988 · J. Bacteriol.; (United States)

OSTI ID:5409431

Widenhorn, K A; Boos, W; Somers, J M; Kay, W W

The tricarboxylate transport operon (tctI) was cloned in Escherichia coli as a 12-kilobase (kb) fragment from an EcoRI library of the Salmonella typhimurium chromosome in lambdagtWES. It was further subcloned as a 12-kb fragment into pACYC184 and as an 8-kb fragment into pBR322. By insertional mutagenesis mediated by lambdaTn5, restriction mapping, and phenotypic testing, the tctI operon was localized to a 4.5-kb region. The tctC gene which encodes a periplasmic binding protein (C-protein) was located near the center of the insert. E. coli/tctI clones on either multicopy or single-copy vectors grew on the same tricarboxylates as S. typhimurium, although unusually long growth lags were observed. E. coli/tctI clones exhibited similar (/sup 14/C) fluorocitrate transport kinetics to those of S. typhimurium, whereas E. coli alone was virtually impermeable to (/sup 14/C) fluorocitrate. The periplasmic C proteins (C1 and C2 isoelectric forms) were produced in prodigious quantities from the cloned strains. Motile E. coli/tctI clones were not chemotactic toward citrate, whereas tctI deletion mutants of S. typhimurium were. Taken together, these observations indicate that tctI is not an operon involved in chemotaxis.

• Research Organization: Univ. of Victoria, British Columbia (Canada)
• OSTI ID: 5409431
• Journal Information: J. Bacteriol.; (United States), Vol. 170:2
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ESCHERICHIA COLI
GENETIC ENGINEERING
GENE OPERONS
DNA-CLONING
SALMONELLA TYPHIMURIUM
CARBON 14 COMPOUNDS
GENETIC MAPPING
KREBS CYCLE
METABOLISM
MUTANTS
PROTEINS
TRACER TECHNIQUES
BACTERIA
CLONING
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAPPING
MICROORGANISMS
ORGANIC COMPOUNDS
SALMONELLA
550401* - Genetics- Tracer Techniques
550701 - Microbiology- Tracer Techniques