Disruption of aldA influences the developmental process in Myxococcus xanthus.
نویسندگان
چکیده
Previously, we identified a gene (aldA) from Myxococcus xanthus, which we suggested encoded the enzyme alanine dehydrogenase on the basis of similarity to known Ald protein sequences (M. J. Ward, H. Lew, A. Treuner-Lange, and D. R. Zusman, J. Bacteriol. 180:5668-5675, 1998). In this study, we have confirmed that aldA does encode a functional alanine dehydrogenase, since it catalyzes the reversible conversion of alanine to pyruvate and ammonia. Whereas an aldA gene disruption mutation did not significantly influence the rate of growth or spreading on a rich medium, AldA was required for growth on a minimal medium containing L-alanine as the major source of carbon. Under developmental conditions, the aldA mutation caused delayed aggregation in both wild-type (DZ2) and FB (DZF1) strains. Poorly formed aggregates and reduced levels of spores were apparent in the DZ2 aldA mutant, even after prolonged development.
منابع مشابه
Glycine betaine biosynthesized from glycine provides an osmolyte for cell growth and spore germination during osmotic stress in Myxococcus xanthus.
Glycine sarcosine methyltransferase (Gsm) and sarcosine dimethylglycine methyltransferase (Sdm) catalyze glycine betaine synthesis from glycine. Disruption of the M. xanthus gsmA (MXAN 7068) or sdmA (MXAN 3190) gene, encoding Gsm or Sdm homologue proteins, respectively, generated mutants that exhibited a longer lag period of growth and delayed spore germination under osmostress.
متن کاملDNA replication during sporulation in Myxococcus xanthus fruiting bodies.
During the developmental process of the Gram-negative soil bacterium Myxococcus xanthus, vegetatively growing rod cells differentiate to ultimately become metabolically quiescent and environmentally resistant myxospores encased within fruiting bodies. This program, initiated by nutrient deprivation, is propagated by both cell-autonomous and cell-nonautonomous signals. Our goal was to determine ...
متن کاملThe Myxococcus xanthus developmentally expressed asgB-dependent genes can be targets of the A signal-generating or A signal-responding pathway.
Functional Myxococcus xanthus A signal-generating and A signal-responding pathways are required for the progression through early multicellular development. To identify genes responsive to these pathways, the expression of eight early developmental genes was analyzed. This examination identified one gene as a target of the A signal-generating pathway and four genes as targets of the A signal-re...
متن کاملA genetic link between light response and multicellular development in the bacterium Myxococcus xanthus.
The Gram-negative bacterium Myxococcus xanthus responds to blue light by producing carotenoid pigments (Car+ phenotype). Genes for carotenoid synthesis lie at two unlinked chromosomal sites, the carC and the carBA operon, but are integrated in a single "light regulon" by the action of common trans-acting regulatory elements. Three known regulatory genes are grouped together at the (light-induci...
متن کاملThe asgE locus is required for cell-cell signalling during Myxococcus xanthus development.
In response to starvation, Myxococcus xanthus undergoes a multicellular developmental process that produces a dome-shaped fruiting body structure filled with differentiated cells called myxospores. Two insertion mutants that block the final stages of fruiting body morphogenesis and reduce sporulation efficiency were isolated and characterized. DNA sequence analysis revealed that the chromosomal...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Journal of bacteriology
دوره 182 2 شماره
صفحات -
تاریخ انتشار 2000