Studies on a Mutant Strain of Escherichia coli which Requires both Methionine and Lysine for Growth
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منابع مشابه
Studies on a mutant strain of Escherichia coli which requires both methionine and lysine for growth.
A mutant of Esckch ia coZi waa isolated which showed a requirement for methionine + lysine when a fairly large inoculum of washed organisms was used. Cystathionine or homocysteine replaced methionine, and diaminopimelic acid replaced lysine; no other amino acid or growth factor was active. The amounts of the amino acids required to promote growth were only about one-tenth of the quantity of met...
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The structure of a mutant Escherichia coli thioredoxin with a glutamic acid substituted for a conserved lysine at position 36 adjacent to the active site has been solved using molecular replacement and refined at 2.0-A resolution to a crystallographic residual of 19.9%. The mutant was crystallized in an orthorhombic space group with one molecule in the asymmetric unit. The structure of the muta...
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Evidence has been presented in this investigation to show that the synthesis of aspartate kinase in Escherichia coli B is regulated by the ratio of the intracellular concentrations of the end products, methionine, threonine, and lysine. LLysine and L-threonine at a concentration of 5 mM repress the enzyme to the extent of 60 to 70% and 15 to 25%, respectively. On the other hand, methionine at a...
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The inability of the methionine requiring Escherichia coli mutant (1-344) to grow in methionine free media containing inorganic sulfur, cystine, or homocystine has been demonstrated (Lampen et al., 1947). While methionine has been shown to be essential for growth, the metabolism of nonmethionine sulfur added to media containing methionine has not been investigated directly. In the results repor...
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ژورنال
عنوان ژورنال: Journal of General Microbiology
سال: 1962
ISSN: 0022-1287
DOI: 10.1099/00221287-27-1-41