PMID:24465756

Citation	Sharma, VK and Casey, TA (2014) Determining the Relative Contribution and Hierarchy of hha and qseBC in the Regulation of Flagellar Motility of Escherichia coli O157:H7. PLoS ONE 9:e85866
Abstract	In recent studies, we demonstrated that a deletion of hha caused increased secretion of locus of enterocyte encoded adherence proteins and reduced motility of enterohemorrhagic Escherichia coli (EHEC) O157:H7. In addition to the importance of hha in positive regulation of motility, a two-component quorum sensing pathway encoded by the qseBC genes has been shown to activate bacterial motility in response to mammalian stress hormones epinephrine and norepinephrine as well as bacterially produced autoinducer-3. In this study, we compared regulatory contribution and hierarchy of hha, a member of the Hha/YmoA family of nucleoid-associated proteins, to that of qseBC in the expression of EHEC O157:H7 motility. Since norepinephrine affects motility of EHEC O157:H7 through a qseBC-encoded two-component quorum sensing signaling, we also determined whether the hha-mediated regulation of motility is affected by norepinephrine and whether this effect is qseBC dependent. We used single (Δhha or ΔqseC) and double (Δhha ΔqseC) deletion mutants to show that hha exerts a greater positive regulatory effect in comparison to qseBC on the expression of motility by EHEC O157:H7. We also show that Hha is hierarchically superior in transcriptional regulation of motility than QseBC because transcription of qseC was significantly reduced in the hha deletion mutant compared to that in the parental and the hha-complemented mutant strains. These results suggest that hha regulates motility of EHEC O157:H7 directly as well as indirectly by controlling the transcription of qseBC.
Links	PubMed Online version:10.1371/journal.pone.0085866
Keywords
edit table

Annotations

Gene product	Qualifier	GO Term	Evidence Code	with/from	Aspect	Extension	Notes	Status
ECOLI:QSEC		GO:0061435: positive regulation of transcription from a mobile element promoter	ECO:0000314:		P		Figure 1. qseC enhances transcription to promote motility.	complete CACAO 9272
ECO57:HHA		GO:2000147: positive regulation of cell motility	ECO:0000315:		P		Figure 1 shows that mutant strains without the hha gene exhibited significantly less motility than the wild-type parental strains.	complete CACAO 10088
ECO57:HHA	involved_in	GO:2000147: positive regulation of cell motility	ECO:0000315: mutant phenotype evidence used in manual assertion		P		Seeded From UniProt	complete
ECOLI:HHA		GO:0061435: positive regulation of transcription from a mobile element promoter	ECO:0000314:		P		Figure 1. Hha ehances transcription to promote motility.	complete CACAO 9270

References

See Help:References for how to manage references in GONUTS.