Article Abstract:
Frankia sequences that have RNA polymerase promoter activity have been studied. Fragments of Frankia strain Arl6 genomic DNA were cloned upstream of a promoterless, Vibrio harveyi lux AB cassette to isolate a section of the DNA that acts as an RNA polymerase promoter. Frankia may use mechanisms similar to those of the enteric bacteria and rhizobia in the expression of nitrogen-regulated genes. A cloned Frankia DNA that directs initiation of transcription in a Frankia cell-free extract from two promoter regions was identified. The upstream promoter, TSP-1, has sequences like those in the canonical Escherichia coli promoter and a Streptomyces promoter element. Frankia are Gram-positive, filamentous pioneer species and are able to fix atmospheric dinitrigen in the free-living state or in symbiosis with various woody plants.
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Article Abstract:
Bordetella bronchiseptica filamentous hemagglutinin (FHA) and its secretion mechanism have been characterized molecularly. FHA secretion is mediated by one outer-membrane accessory protein, FhaC and is generally thought to be the main adhesin of B. pertussis. It is in significantly lower levels in B bronchiseptica. Genes that encode FHA and FhaC in B. bronchiseptica have been characterized. They are very like those of b. pertussis.
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Article Abstract:
Thermoprotection by glycine choline and betaine is discussed. Based on a new study, it seems that in addition to working as an osmoprotectant, glycine betaine acts in thermoprotection of bacteria. Glycine betaine is known to act as a protein stabilizer, which prompted this study.
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