Independent and Interchangeable Multimerization Domains of the AbrB, Abh, and SpoVT Global Regulatory Proteins

Yao, Fude; Strauch, Mark A.

doi:10.1128/jb.187.18.6354-6362.2005

Cited by 20 publications

(23 citation statements)

References 34 publications

(45 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since CwlD is essential for the generation of the cortex-specific modification, muramic acid ␦-lactam (MAL) (35), it is possible that the cortical PG in spoVT spores has less MAL than that in wild-type spores. If this is the case, even though SpoVT appears to repress expression of one cortex-lytic enzyme (CLE), SleB (42), the degradation of cortex PG might be slower during germination of spoVT spores, since MAL is the recognition element for SleB as well as the other redundant CLE, CwlJ (34,35). Indeed, spoVT spores have significantly longer ⌬T lysis s for both AGFK and L-valine germination, and SpoVT is also an activator of a spore cortex protein, CoxA (41), although the function of this protein is not known.…”

Section: Figmentioning

confidence: 99%

“…However, there is no knowledge of how G levels may vary between individual spores or how much stochasticity might affect an individual spore's G levels. There is also a forespore-specific transcriptional regulatory protein, SpoVT, which modulates the expression of a number of G -dependent genes (1,3,38,41,42). SpoVT can be either a positive or a negative regulator of gene expression, and in spores prepared by resuspension in a poor medium, SpoVT represses levels of expression of operons encoding GRs ϳ3-fold and slightly stimulates the expression of the forespore-specific spoVA operon that encodes a number of proteins likely involved in spore germination by allowing the spore's large depot (ϳ20% of spore core dry weight) of pyridine-2,6-dicarboxylic acid (dipicolinic acid [DPA]) to leave the germinating spore, one of the earliest events in spore germination.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Effects of the SpoVT Regulatory Protein on the Germination and Germination Protein Levels of Spores of Bacillus subtilis

et al. 2012

View full text Add to dashboard Cite

bBacillus subtilis isolates lacking the SpoVT protein, which regulates gene expression in developing forespores, gave spores that released their dipicolinic acid (DPA) via germinant receptor (GR)-dependent germination more rapidly than wild-type spores. Non-GR-dependent germination via dodecylamine was more rapid with spoVT spores, but germination via Ca-DPA was slower. The effects of a spoVT mutation on spore germination were seen with spores made in rich and poor media, and levels of SpoVTLacZ were elevated 2-fold in poor-medium spores; however, elevated SpoVT levels were not the only cause of the slower GR-dependent germination of poor-medium spores. The spoVT spores had >5-fold higher GerA GR levels, ϳ2-fold elevated GerB GR levels, wild-type levels of a GerK GR subunit and the GerD protein required for normal GR-dependent germination, ϳ2.5-fold lower levels of the SpoVAD protein involved in DPA release in spore germination, and 30% lower levels of DNA protective ␣/␤-type small, acid-soluble spore proteins. With one exception, the effects on protein levels in spoVT spores are consistent with the effects of SpoVT on forespore transcription. The spoVT spores were also more sensitive to UV radiation and outgrew slowly. While spoVT spores' elevated GR levels were consistent with their more rapid GR-dependent germination, detailed analysis of the results suggested that there is another gene product crucial for GR-dependent spore germination that is upregulated in the absence of SpoVT. Overall, these results indicate that SpoVT levels during spore formation have a major impact on the germination and the resistance of the resultant spores.

show abstract

Section: Figmentioning

confidence: 99%

mentioning

confidence: 99%

Effects of the SpoVT Regulatory Protein on the Germination and Germination Protein Levels of Spores of Bacillus subtilis

et al. 2012

View full text Add to dashboard Cite

show abstract

“…However, an in-depth inspection performed with the PSI-BLAST and CDD searches and secondary structure predictions (16) highlighted the presence of a SpoVT/AbrB-like domain in the translated protein. This motif is present in a family of prokaryotic factors demonstrated to be repressors, activators, or ambiactive, depending on the specific case (18,62).…”

Section: Resultsmentioning

confidence: 99%

“…The rep locus is comprised of four ORFs: ORF c68 encodes a putative transcription factor containing an SpoVT/AbrBlike domain (18,62), typical of a bacterial family of transcription factors. Since this kind of transcription factor gene is missing on other prokaryotic plasmids and is present on the genomes of pSSVi, of STSV1 (Sulfolobus tengchongensis spindle-shaped virus), and SIFV (Sulfolobus islandicus filamentous virus) (40), it is tempting to speculate that acquisition by the pSSVx genome of ORFc68 as well as of ORF154 to ORF288 has been crucial for the development of a viral nature and for the ability to respond to diverse viral stimuli.…”

Section: Discussionmentioning

confidence: 99%

Transcriptional Analysis of the Genetic Element pSSVx: Differential and Temporal Regulation of Gene Expression Reveals Correlation between Transcription and Replication

et al. 2007

View full text Add to dashboard Cite

pSSVx from Sulfolobus islandicus strain REY15/4 is a hybrid between a plasmid and a fusellovirus. A systematic study performed by a combination of Northern blot analysis, primer extension, and reverse transcriptase PCR revealed the presence of nine major transcripts whose expression was differentially and temporally regulated over the growth cycle of S. islandicus. The map positions of the RNAs as well as the clockwise and the anticlockwise directions of their transcription were determined. Some genes were clustered and appeared to be transcribed as polycistronic messengers, among which one long transcriptional unit comprised the genes for the plasmid copy number control protein ORF60 (CopG), ORF91, and the replication protein ORF892 (RepA). We propose that a termination readthrough mechanism might be responsible for the formation of more than one RNA species from a single 5 end and therefore that the nine different RNAs corresponded to only seven different transcriptional starts. Three transcripts, ORF76 and two antisense RNAs, countertranscribed RNA1 (ctRNA1) and ctRNA2, were found to be specifically expressed during (and hence correlated to) the phase in which the pSSVx copy number is kept under stringent control, as they were completely switched off upon the onset of the induction of replication.Whereas major studies on viral systems in Bacteria and Eukarya have shed sufficient light on basic and regulated gene expression in these organisms, very little regarding the elucidation of the mechanisms of viral gene expression and regulation in hyperthermophilic Archaea has been addressed. A few archaeal viruses have been investigated in depth at molecular and physiological levels (23,25,48,53). These viruses are known to be highly unusual in terms of morphology and genome structure/sequence (38,39,40,41,45). A survey of the extrachromosomal elements in the hyperthermophilic crenarchaeon Sulfolobus (64, 65) has revealed the existence of many new viruses, with the Fuselloviridae being the most common family among the Sulfolobales to date (37). Sulfolobus spindleshaped virus 1 (SSV1) is the best-studied member of this family, and it behaves as a temperate virus both in Sulfolobus shibatae and in the nonnatural but related Sulfolobus solfataricus host (53); infection, integration of DNA into the host chromosome, and the production of virions cause apparently no phenotype change but do cause a significant growth retardation of the host cells, which can be visualized as turbid plaques on plated lawns of indicator host cells around propagation foci (53, 65).Transcription studies conducted on SSV1 have pointed out that the copy number of the episomal DNA as well as the virus titer remain essentially constant in the unirradiated host (48). DNA replication increases after induction by UV or other DNA-damaging agents and seems to be mediated by transcription at the promoter T ind (48,53). Furthermore, the structural genes of SSV1 are constitutively and coordinately transcribed in nonirradiated cells, and the amount of these...

show abstract

“…Several charged residues in this domain, including the positively charged Lys 67 , Arg 75 , and Arg 83 residues, were identified to be crucial, which indicated that these positively charged residues might contribute to DNA binding by interacting with the negatively charged DNA and demonstrated a critical involvement of the AbrB-like domain in the negative regulatory role of the PhaR in H. mediterranei. AbrB and AbrB-like proteins usually function as dimers or tetramers (44,47). In bacteria, PhaR was also shown to form a tetramer in vitro (43).…”

Section: Discussionmentioning

confidence: 99%

A Novel DNA-Binding Protein, PhaR, Plays a Central Role in the Regulation of Polyhydroxyalkanoate Accumulation and Granule Formation in the Haloarchaeon Haloferax mediterranei

Cai

Zhao

et al. 2015

Appl Environ Microbiol

View full text Add to dashboard Cite

c Polyhydroxyalkanoates (PHAs) are synthesized and assembled as PHA granules that undergo well-regulated formation in many microorganisms. However, this regulation remains unclear in haloarchaea. In this study, we identified a PHA granule-associated regulator (PhaR) that negatively regulates the expression of both its own gene and the granule structural gene phaP in the same operon (phaRP) in Haloferax mediterranei. Chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) assays demonstrated a significant interaction between PhaR and the phaRP promoter in vivo. Scanning mutagenesis of the phaRP promoter revealed a specific cis-element as the possible binding position of the PhaR. The haloarchaeal homologs of the PhaR contain a novel conserved domain that belongs to a swapped-hairpin barrel fold family found in AbrB-like proteins. Amino acid substitution indicated that this AbrB-like domain is critical for the repression activity of PhaR. In addition, the phaRP promoter had a weaker activity in the PHA-negative strains, implying a function of the PHA granules in titration of the PhaR. Moreover, the H. mediterranei strain lacking phaR was deficient in PHA accumulation and produced granules with irregular shapes. Interestingly, the PhaR itself can promote PHA synthesis and granule formation in a PhaP-independent manner. Collectively, our results demonstrated that the haloarchaeal PhaR is a novel bifunctional protein that plays the central role in the regulation of PHA accumulation and granule formation in H. mediterranei. P olyhydroxyalkanoates (PHAs) are biodegradable polyesters synthesized by most genera of bacteria (1, 2) and some archaea (3-5). PHAs are accumulated as storage compounds of energy and carbon under imbalanced growth conditions (i.e., when nutrients such as nitrogen, phosphorus, or oxygen are limited but the carbon sources are in excess) (6).PHAs are often deposited in the cytoplasm as water-insoluble inclusions that are called PHA granules (6). Native PHA granules are found to be composed of 97.5% PHA, 2% proteins, and likely some amount of lipids (7). At least four types of proteins were found to be the PHA granule-associated proteins (PGAPs) in bacteria: PHA synthases, PHA depolymerases, regulators, and structural proteins (phasins [PhaPs]) (8, 9). In recent years, increasing new roles have been found for the PGAPs. Besides the classical phasin role of preventing PHA granules from coalescing, two distinct phasin-like proteins, PhaM and PhaF, have also been characterized as being crucial for granule distribution during cell division (10, 11).The PGAPs play important roles in PHA synthesis, PHA utilization, and granule formation and distribution (8, 9, 12), among which the regulatory proteins are responsible for ensuring the proper formation of PHA granules by influencing the expression of both phasins and themselves (13)(14)(15)(16)(17). A classic regulation model was presented in a poly(3-hydroxybutyrate) (PHB [a type of PHA])-accumulating bacterium, Ralstonia eutropha H16 (9). Briefly, the cy...

show abstract

Independent and Interchangeable Multimerization Domains of the AbrB, Abh, and SpoVT Global Regulatory Proteins

Cited by 20 publications

References 34 publications

Effects of the SpoVT Regulatory Protein on the Germination and Germination Protein Levels of Spores of Bacillus subtilis

Effects of the SpoVT Regulatory Protein on the Germination and Germination Protein Levels of Spores of Bacillus subtilis

Transcriptional Analysis of the Genetic Element pSSVx: Differential and Temporal Regulation of Gene Expression Reveals Correlation between Transcription and Replication

A Novel DNA-Binding Protein, PhaR, Plays a Central Role in the Regulation of Polyhydroxyalkanoate Accumulation and Granule Formation in the Haloarchaeon Haloferax mediterranei

Contact Info

Product

Resources

About