Salt-tolerant and thermostable glutaminases of cryptococcus species form a new glutaminase family.

Genes encoding salt-tolerant and thermostable glutaminases were isolated from Cryptococcus species. The glutaminase gene, CngahA, from C. nodaensis NISL-3771 was 2,052 bp in length and encoded a 684-amino acid protein.

Transcriptional regulation of genes on the non-syntenic blocks of Aspergillus oryzae and its functional relationship to solid-state cultivation.

Transcriptome analysis revealed close relationship between solid-state cultivation and the transcriptional regulation of the genes on the non-syntenic blocks (NSBs), which were characterized by the comparison of Aspergillus oryzae genome with those of Aspergillus fumigatus and Aspergillus nidulans. Average expression ratio of the genes on NSBs in solid-state cultivation was significantly higher than that on the syntenic blocks (SBs). Of the induced genes, the genes relating to metabolism, which are highly enriched on NSBs, most contributed to the NSB-specific induction.

Increased production of pyruvic acid by Escherichia coli RNase G mutants in combination with cra mutations.

The Escherichia coli RNase G is known as an endoribonuclease responsible for the 5'-end maturation of 16S rRNA and degradation of several specific mRNAs such as adhE and eno mRNAs. In this study, we found that an RNase G mutant derived from the MC1061 strain did not grow on a glucose minimal medium. Genetic analysis revealed that simultaneous defects of cra and ilvIH, encoding a transcriptional regulator of glycolysis/gluconeogenesis and one of isozymes of acetohydroxy acid synthase, respectively, were required for this phenomenon to occur.

RNase E is required for induction of the glutamate-dependent acid resistance system in Escherichia coli.

The Escherichia coli RNase E is an essential endoribonuclease involved in processing and/or degradation of rRNAs, tRNAs, and non-coding small RNAs as well as many mRNAs. It is known that RNase E activity is somehow regulated by an RNA-binding protein Hfq, at least in some cases. We searched for proteins that showed changes in expression in both hfq::cat and rne-1 mutant cells as compared with the wild type, and found that a protein band of 49-kDa decreased in these mutant cells at 42 degrees C, the restrictive temperature for rne-1.

RNase G-dependent degradation of the eno mRNA encoding a glycolysis enzyme enolase in Escherichia coli.

Escherichia coli RNase G, encoded by the rng gene, is involved in the processing of 16S rRNA and degradation of the adhE mRNA encoding a fermentative alcohol dehydrogenase. In a search for the intracellular target RNAs of RNase G other than the 16S rRNA precursor and adhE mRNA, total cellular proteins from rng+ and rng::cat cells were compared by two-dimensional gel electrophoresis. The amount of enolase encoded by the eno gene reproducibly increased two- to three-fold in the rng::cat mutant strain compared with the rng+ parent strain.

Extensive overproduction of the AdhE protein by rng mutations depends on mutations in the cra gene or in the Cra-box of the adhE promoter.

Escherichia coli RNase G encoded by the rng gene is involved in degradation of adhE mRNA. Overproduction of the AdhE protein by rng mutants was found to depend on the genetic background of strains derived from DC272 (adhC81) or MC1061. We found that DC272 carried a point mutation in the Cra-binding site of the adhE promoter.