Disease relevance of uspA

• The increased expression of the uspA gene of Escherichia coli is an essential part of the cell's response to growth arrest [1].
• The procedure involves amplification of the E. coli-specific universal stress protein A (uspA) gene (uspa-PCR), with the primer pair described by other authors, which allows differentiation of E. coli (STEC and non-STEC) from other gram-negative bacteria followed by identification of the main genetic virulence traits of the uspA-positive isolates [2].

High impact information on uspA

• An insertion in the cell division gene ftsK upregulates uspA in a recA-dependent manner [3].
• Moreover, the uspA mutation results in an increased sensitivity of cells to carbon-source starvation (i.e. glucose, glycerol or succinate depletion) [4].
• The amino acid sequence, deduced from the nucleotide sequence of the uspA gene, shows no significant homology with any other known protein [5].
• The uspA gene maps at 77 min on the E. coli W3110 chromosome, and is transcribed in a clockwise direction [5].
• We demonstrate that the product of uspA is a serine and threonine phosphoprotein [6].

Biological context of uspA

• All the fad-lacZ fusions examined (fadBA, fadL, and fadD) are increasingly expressed in stationary phase with kinetics similar to that of the increased expression of uspA [1].
• The open reading frame immediately upstream of uspA is demonstrated to encode a 14-kDa protein which we named UspB (universal stress protein B) because of its general responsiveness to different starvation and stress conditions [7].
• A plasmid with the structural uspA gene under the control of a tac promoter was used to study the effects of altering uspA expression levels under various growth conditions [8].
• An industrial high cell density fed-batch cultivation on the basis of the suggested fed-batch protocol and the uspA promoter gave a final beta-galatosidase concentration of 7 g/L and a final cell concentration of 65 g/L [9].

Anatomical context of uspA

• Best results were obtained with a moderate copy number vector (15-60 copies) bearing the uspA promoter, reaching 4.6 mg/g dry cell weight (DCW) of ZZ-proinsulin secreted to the periplasm and 1.9 mg/g DCW secreted to the culture medium [10].

Associations of uspA with chemical compounds

• Transcription of uspA is derepressed during exponential growth in fadR null mutants or by including the fatty acid oleate in the growth medium of FadR+ cells [1].
• The uspA mutant appears to dissimilate glucose at an elevated rate that is not commensurate with its biosynthetic processes [11].
• The data indicate that the sigma(70) regulated promoter, uspA, although affected by the alarmone guanosine tetraphosphate, ppGpp, worked partly in a similar manner to constitutive promoters [9].
• Inactivation of uspA in S. typhimurium C5, lead to increased susceptibility to stress conditions [12].

Other interactions of uspA

• Thus, uspA is a member of the fadR regulon [1].
• Thus, a mutation in the cell division gene, ftsK, uncouples the otherwise coordinated induction of sigma(S)-dependent genes and the universal stress response gene, uspA, during entry into stationary phase [13].
• Cryotolerance induced by starvation of TSB- and LB-grown E. coli was correlated with the expression of genes involved in general stress response pathways, such as uspA, grpE, and rpoS [14].
• In contrast to uspA, stationary-phase induction of uspB requires the sigma factor sigmaS [7].

Analytical, diagnostic and therapeutic context of uspA

• The results of DNA footprinting analysis show that FadR binds downstream of the uspA promoter in the noncoding region [1].
• As was demonstrated by two-dimensional gel electrophoresis, increased uspA expression caused global changes in the pattern of protein synthesis [8].
• We quantified the copy numbers of E. coli in the urine of patients with UTI by using a real-time PCR assay (the TaqMan system) targeting uspA genes in genomic DNAs isolated from urine samples (n=200) [15].

References