Mutant strains of Escherichia coli K12 that use D-amino acids.
نویسندگان
چکیده
A series of mutations has been isolated that confer upon amino-acid auxotrophs of Escherichia coli K-12 the ability to grow when fed various D-amino acids. Several distinct systems, mediating cellular use of the D-isomers of leucine, histidine, phenylalanine, tyrosine, tryptophan, isoleucine, and valine, can be mutationally activated. Mutations leading to D-tryptophan use (dadR) all map near purB. They result in high activities of an enzyme that deaminates D-amino acids. Neither the enzymes of the tryptophan biosynthetic pathway nor tryptophanase (EC 4.2.1.e) are involved in D-tryptophan utilization.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 68 10 شماره
صفحات -
تاریخ انتشار 1971