Extragenic suppression of the requirement for diaminopimelate in diaminopimelate auxotrophs of Mycobacterium smegmatis.
نویسندگان
چکیده
Mycobacteria, like many prokaryotes, have a peptidoglycan with peptides composed of L-alanine (or glycine), D-iso-glutamine, meso-diaminopimelate, and D-alanine. We sought to study mycobacterial peptidoglycan biosynthesis by constructing diaminopimelate (DAP) auxotrophs of Mycobacterium smegmatis and then isolating spontaneous mutants of these auxotrophs that can grow in the absence of DAP. Here we report the isolation and characterization of seven classes of spontaneous M. smegmatis mutants with extragenic mutations that can suppress the DAP requirement of DAP auxotrophs.
منابع مشابه
An unusual mutation results in the replacement of diaminopimelate with lanthionine in the peptidoglycan of a mutant strain of Mycobacterium smegmatis.
Mycobacterial peptidoglycan contains L-alanyl-D-iso-glutaminyl-meso-diaminopimelyl-D-alanyl-D-alanine peptides, with the exception of the peptidoglycan of Mycobacterium leprae, in which glycine replaces the L-alanyl residue. The third-position amino acid of the peptides is where peptidoglycan cross-linking occurs, either between the meso-diaminopimelate (DAP) moiety of one peptide and the penul...
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In some bacterial species and photosynthetic cohorts, including algae, the enzyme L,L-diaminopimelate aminotransferase (DapL) (E.C. 2.6.1.83) is involved in the anabolism of the essential amino acid L-lysine. DapL catalyzes the conversion of tetrahydrodipicolinate (THDPA) to L,L-diaminopimelate (L,L-DAP), in one step bypassing the DapD, DapC and DapE enzymatic reactions present in the acyl DAP ...
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ورودعنوان ژورنال:
- FEMS microbiology letters
دوره 225 1 شماره
صفحات -
تاریخ انتشار 2003