Coordination of Enzyme Synthesis in the l-Arabinose Operon in Escherichia coli

Patrick, James W.; Lee, Nancy; Barnes, Nora B.; Englesberg, Ellis

doi:10.1016/s0021-9258(18)61974-x

Cited by 10 publications

(2 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The subunits have a molecular weight of 60,000, which suggests that the native enzyme is composed of six identical monomers (14). In additional studies, Patrick et al (15) found that the intrinsic activity of isomerase was not always the same from culture to culture even though the levels of enzyme protein were comparable when tested against anti-isomerase serum. The difference in intrinsic activity was attributed to a dependence upon manganous ions during synthesis of the enzyme at some step beyond the level of translation.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

l -Arabinose Isomerase Formation in a Conditional Mutant of Gene araA of Escherichia coli B/r

1972

View full text Add to dashboard Cite

A temperature-sensitive mutant of Escherichia coli in which the synthesis of l -arabinose isomerase is blocked during growth at 42 C was found to possess the following properties. (i) The mutation occurred in the structural gene for the isomerase, gene araA . (ii) During growth at elevated temperatures the mutant accumulates a product which is a precursor to the active enzyme. (iii) The precursor produced at 42 C is slowly converted to active enzyme at 28 C in the absence of protein and ribonucleic acid synthesis. It is concluded that the mutation results in a change in the structure of isomerase which causes formation of active enzyme to be thermolabile at a step beyond the level of translation.

show abstract

Section: Discussionmentioning

confidence: 99%

“…Heat inactivation studies. Partially purified Larabinose isomerase was studied for heat inactivation by previously described methods (15). Crude extracts were mixed with MnCl2 (0.05 M final concentration) and held overnight in ice.…”

mentioning

confidence: 99%

l -Arabinose Isomerase Formation in a Conditional Mutant of Gene araA of Escherichia coli B/r

1972

View full text Add to dashboard Cite

show abstract

The site for catabolite deactivation in the L-arabinose BAD operon in Escherichia coli B/r

et al. 1976

View full text Add to dashboard Cite

A series of deletions beginning in the leu operon and continuing into the araC gene and also into the ara controlling site region were analyzed in reciprocal merodiploids, e.g., F' A2Cc67/B24delta719, F' B24delta719/A2Cc67, for their effects on catabolite deactivation (CD). The results of these experiments are consistent with placing the catabolite gene activator-cyclic AMP sensitive site in the controlling site region between araB and araO. With a deletion mutant, delta1109, that places araBAD under leu control when transcription begins at leuP, the araBAD operon is immune to CD even though araCGA, araP and araI are intact and functional. To focus attention on the fine structure and related functions of this region we propose that the three proteins that function therein have separate sites of action: araI (initiator-site for activator), araP (promoter-site for RNA polymerase) and ara(CGA) (catabolite gene activator-site for CGA-cAMP). None of the eighteen initiator constitutive mutants (Ic) tested have any significant effect on catabolite derepression or on the maximal level of expression of the operon supporting the view that the araI site may be distinct from araP and ARA(CGA). A series of constitutive mutants in the araC gene (Cc) also have no pronounced effect on catabolite deactivation.

show abstract

Current studies on biological tagatose production using l-arabinose isomerase: a review and future perspective

Kim

2004

Appl Microbiol Biotechnol

129

View full text Add to dashboard Cite

D-Tagatose is a hexoketose monosaccharide sweetener, which is an isomer of D-galactose and is rarely found in nature. Recently, there has been industrial interest in D-tagatose as a low-calorie sugar-substituting sweetener. This article describes the properties and metabolism of tagatose as well as its commercial importance. The comparison between the biological tagatose production and the chemical production was reviewed based on the example of the glucose isomerization into fructose. The industrial problems facing its commercial application is described and evolving potential solutions are suggested.

show abstract

Coordination of Enzyme Synthesis in the l-Arabinose Operon in Escherichia coli

Cited by 10 publications

References 8 publications

l -Arabinose Isomerase Formation in a Conditional Mutant of Gene araA of Escherichia coli B/r

l -Arabinose Isomerase Formation in a Conditional Mutant of Gene araA of Escherichia coli B/r

The site for catabolite deactivation in the L-arabinose BAD operon in Escherichia coli B/r

Current studies on biological tagatose production using l-arabinose isomerase: a review and future perspective

Contact Info

Product

Resources

About