Role of phosphoenolpyruvate-phosphotransferase in glucose utilization by bacilli

1972 ◽  
Vol 182 (1067) ◽  
pp. 171-181 ◽  
Keyword(s):  
Bacillus Licheniformis ◽  
Glucose Utilization ◽  
Glycolytic Enzymes ◽  
Wild Type ◽  
Phosphotransferase System ◽  
Wild Type Phenotype

The growth of mutant Z4 of Bacillus licheniformis on glucose and on a number of other carbohydrates is impaired, but growth on fructose, glycerol and on glucuronate is not. There are no significant differences between the mutant and its parent in the levels of glycolytic enzymes and in the ability of the organisms to take up labelled fructose; in contrast, the mutant takes up and phosphorylates labelled glucose, and its analogues methyl α -glucoside and 2-deoxyglucose, to a much smaller extent than does the wild-type. Extracts of the mutant are virtually devoid of the inducible phosphoenolpyruvate-dependent glucose phosphotransferase present in the parent, though fructose phosphotransferase activity is present in both organisms. Revertants of Z4 , selected for growth on glucose, fully regain the wild-type phenotype. These results show that the phosphotransferase system plays a necessary role in the utilization of glucose by bacilli.

scholarly journals Association of intronic DNA methylation and hydroxymethylation alterations in the epigenetic etiology of dilated cardiomyopathy

2019 ◽  
Vol 317 (1) ◽  
pp. H168-H180 ◽  
Author(s):  
Ali M. Tabish ◽  
Mohammed Arif ◽  
Taejeong Song ◽  
Zaher Elbeck ◽  
Richard C. Becker ◽  
...  
Keyword(s):  
Gene Expression ◽  
Dna Methylation ◽  
Dilated Cardiomyopathy ◽  
Cardiac Remodeling ◽  
Rna Seq ◽  
Wild Type ◽  
Kegg Pathways ◽  
Wild Type Phenotype ◽  
Gene Expression Levels

In this study, we investigated the role of DNA methylation [5-methylcytosine (5mC)] and 5-hydroxymethylcytosine (5hmC), epigenetic modifications that regulate gene activity, in dilated cardiomyopathy (DCM). A MYBPC3 mutant mouse model of DCM was compared with wild type and used to profile genomic 5mC and 5hmC changes by Chip-seq, and gene expression levels were analyzed by RNA-seq. Both 5mC-altered genes (957) and 5hmC-altered genes (2,022) were identified in DCM hearts. Diverse gene ontology and KEGG pathways were enriched for DCM phenotypes, such as inflammation, tissue fibrosis, cell death, cardiac remodeling, cardiomyocyte growth, and differentiation, as well as sarcomere structure. Hierarchical clustering of mapped genes affected by 5mC and 5hmC clearly differentiated DCM from wild-type phenotype. Based on these data, we propose that genomewide 5mC and 5hmC contents may play a major role in DCM pathogenesis. NEW & NOTEWORTHY Our data demonstrate that development of dilated cardiomyopathy in mice is associated with significant epigenetic changes, specifically in intronic regions, which, when combined with gene expression profiling data, highlight key signaling pathways involved in pathological cardiac remodeling and heart contractile dysfunction.

scholarly journals The Peptidoglycan Hydrolase of Staphylococcus aureus Bacteriophage ϕ11 Plays a Structural Role in the Viral Particle

2013 ◽  
Vol 79 (19) ◽  
pp. 6187-6190 ◽  
Author(s):  
Lorena Rodríguez-Rubio ◽  
Nuria Quiles-Puchalt ◽  
Beatriz Martínez ◽  
Ana Rodríguez ◽  
José R. Penadés ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Burst Size ◽  
Wild Type ◽  
Content Type ◽  
Wild Type Phenotype ◽  
Viral Particles ◽  
Peptidoglycan Hydrolases ◽  
Host Lysis ◽  
Phage Growth

ABSTRACTThe role of virion-associated peptidoglycan hydrolases (VAPGHs) in the phage infection cycle is not clear. gp49, the VAPGH fromStaphylococcus aureusphage ϕ11, is not essential for phage growth but stabilizes the viral particles. ϕ11Δ49 phages showed a reduced burst size and delayed host lysis. Complementation of gp49 with HydH5 from bacteriophage vB_SauS-phiIPLA88 restored the wild-type phenotype.

CX3CR1 is required for monocyte homeostasis and atherogenesis by promoting cell survival

Blood ◽  
2009 ◽  
Vol 113 (4) ◽  
pp. 963-972 ◽  
Author(s):  
Limor Landsman ◽  
Liat Bar-On ◽  
Alma Zernecke ◽  
Ki-Wook Kim ◽  
Rita Krauthgamer ◽  
...  
Keyword(s):  
Mechanistic Explanation ◽  
Foam Cells ◽  
Blood Monocytes ◽  
Wild Type ◽  
Inflammatory Conditions ◽  
Survival Signal ◽  
Wild Type Phenotype ◽  
Atherosclerosis Development ◽  
Chemokine Family

Abstract CX3CR1 is a chemokine receptor with a single ligand, the membrane-tethered chemokine CX3CL1 (fractalkine). All blood monocytes express CX3CR1, but its levels differ between the main 2 subsets, with human CD16+ and murine Gr1low monocytes being CX3CR1hi. Here, we report that absence of either CX3CR1 or CX3CL1 results in a significant reduction of Gr1low blood monocyte levels under both steady-state and inflammatory conditions. Introduction of a Bcl2 transgene restored the wild-type phenotype, suggesting that the CX3C axis provides an essential survival signal. Supporting this notion, we show that CX3CL1 specifically rescues cultured human monocytes from induced cell death. Human CX3CR1 gene polymorphisms are risk factors for atherosclerosis and mice deficient for the CX3C receptor or ligand are relatively protected from atherosclerosis development. However, the mechanistic role of CX3CR1 in atherogenesis remains unclear. Here, we show that enforced survival of monocytes and plaque-resident phagocytes, including foam cells, restored atherogenesis in CX3CR1-deficent mice. The fact that CX3CL1-CX3CR1 interactions confer an essential survival signal, whose absence leads to increased death of monocytes and/or foam cells, might provide a mechanistic explanation for the role of the CX3C chemokine family in atherogenesis.

scholarly journals Hepatitis B Virus pX Targets TFIIB in Transcription Coactivation

1998 ◽  
Vol 18 (3) ◽  
pp. 1562-1569 ◽  
Author(s):  
Izhak Haviv ◽  
Meir Shamay ◽  
Gilad Doitsh ◽  
Yosef Shaul
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Rna Polymerase Ii ◽  
Wild Type ◽  
Nuclear Extracts ◽  
Wild Type Phenotype ◽  
B Virus

ABSTRACT pX, the hepatitis B virus (HBV)-encoded regulator, coactivates transcription through an unknown mechanism. pX interacts with several components of the transcription machinery, including certain activators, TFIIB, TFIIH, and the RNA polymerase II (POLII) enzyme. We show that pX localizes in the nucleus and coimmunoprecipitates with TFIIB from nuclear extracts. We used TFIIB mutants inactive in binding either POLII or TATA binding protein to study the role of TFIIB-pX interaction in transcription coactivation. pX was able to bind the former type of TFIIB mutant and not the latter. Neither of these sets of TFIIB mutants supports transcription. Remarkably, the latter TFIIB mutants fully block pX activity, suggesting the role of TFIIB in pX-mediated coactivation. By contrast, in the presence of pX, TFIIB mutants with disrupted POLII binding acquire the wild-type phenotype, both in vivo and in vitro. These results suggest that pX may establish the otherwise inefficient TFIIB mutant-POLII interaction, by acting as a molecular bridge. Collectively, our results demonstrate that TFIIB is the in vivo target of pX.

scholarly journals Utilization of gluconate by Escherichia coli. A role of adenosine 3′:5′-cyclic monophosphate in the induction of gluconate catabolism

1975 ◽  
Vol 150 (1) ◽  
pp. 123-128 ◽  
Author(s):  
B Bächi ◽  
H L Kornberg
Keyword(s):  
Escherichia Coli ◽  
Cyclic Amp ◽  
Uptake System ◽  
Wild Type ◽  
Methyl Glyoxal ◽  
Cyclic Monophosphate ◽  
Inhibition Of Growth ◽  
Wild Type Phenotype ◽  
Specific Activities

1. Cultures of Escherichia coli growing on gluconate use both gluconate and glucose when glucose is added. 2. Glycerol-grown cells adapt to gluconate utilization even in media containing glucose as well as gluconate. 3. The rates of gluconate utilization by cells growing on a mixture of glucose and gluconate, and the specific activities of the gluconate uptake system and of gluconate kinase, are greater if adenosine 3′:5′-cyclic monophosphate (cyclic AMP) is present in the medium than in its absence. 4. Growth on media containing gluconate and cyclic AMP is accompanied by the formation of methyl glyoxal and pyruvate, and progressive inhibition of growth. 5. A mutant devoid of adenylate cyclase activity (cya) grew well on glucose in the absence of exogenous cyclic AMP but grew only poorly on gluconate; neither the gluconate uptake system nor gluconate kinase was adequately induced. The addition of cyclic AMP promoted growth on gluconate and facilitated the induction of proteins required for gluconate catabolism. 6. Phage Pl-mediated transduction of cya+ into the cya-mutant also restored the wild-type phenotype in its ability to adapt to gluconate utilization.

scholarly journals Role of ptsO in Carbon-Mediated Inhibition of the Pu Promoter Belonging to the pWW0Pseudomonas putida Plasmid

2001 ◽  
Vol 183 (17) ◽  
pp. 5128-5133 ◽  
Author(s):  
Ildefonso Cases ◽  
Francisco Velázquez ◽  
Vı́ctor de Lorenzo
Keyword(s):  
Gene Dosage ◽  
Sugar Transport ◽  
Regulatory Elements ◽  
Open Reading Frames ◽  
Type I ◽  
Phosphotransferase System ◽  
Wild Type Phenotype ◽  
Genomic Search ◽  
Regulatory Functions

ABSTRACT An investigation was made into the role of the ptsOgene in carbon source inhibition of the Pu promoter belonging to the Pseudomonas putida upper TOL (toluene degradation) operon. ptsO is coexpressed withptsN, the loss of which is known to renderPu unresponsive to glucose. Both ptsN andptsO, coding for the phosphoenolpyruvate:sugar phosphotransferase system (PTS) family proteins IIANtr and NPr, respectively, have been mapped adjacent to the rpoN gene of P. putida. The roles of these two genes in the responses of Pu to glucose were monitored by lacZ reporter technology with a P. putida strain engineered with all regulatory elements in monocopy gene dosage. In cells lacking ptsO,Pu activity seemed to be inhibited even in the absence of glucose. A functional relationship with ptsNwas revealed by the phenotype of a double ptsN ptsOmutant that was equivalent to the phenotype of a mutant with a singleptsN disruption. Moreover, phosphorylation of the product of ptsO seemed to be required for C inhibition of Pu, since an H15A change in the NPr sequence that prevents phosphorylation of this conserved amino acid residue did not restore the wild-type phenotype. A genomic search for proteins able to phosphorylate ptsO revealed the presence of two open reading frames, designated ptsP and mtp, with the potential to encode PTS type I enzymes in P. putida. However, neither an insertion in ptsPnor an insertion in mtp resulted in a detectable change in inhibition of Pu by glucose. These results indicate that some PTS proteins have regulatory functions in P. putida that are independent of their recognized role in sugar transport in other bacteria.

scholarly journals Alternative Transcription Factor ςB Is Involved in Regulation of Biofilm Expression in a Staphylococcus aureusMucosal Isolate

2000 ◽  
Vol 182 (23) ◽  
pp. 6824-6826 ◽  
Author(s):  
Shwan Rachid ◽  
Knut Ohlsen ◽  
Ursula Wallner ◽  
Jörg Hacker ◽  
Michael Hecker ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Critical Role ◽  
Wild Type ◽  
Global Regulator ◽  
Expression Plasmid ◽  
Wild Type Phenotype ◽  
Alternative Transcription ◽  
Negative Phenotype ◽  
Combined Data

ABSTRACT Osmotic stress was found to induce biofilm formation in aStaphylococcus aureus mucosal isolate. Inactivation of a global regulator of the bacterial stress response, the alternative transcription factor ςB, resulted in a biofilm-negative phenotype and loss of salt-induced biofilm production. Complementation of the mutant strain with an expression plasmid encoding ςB completely restored the wild-type phenotype. The combined data suggest a critical role of ςB in S. aureus biofilm regulation under environmental stress conditions.

scholarly journals The Type III–Secreted Protein NopE1 Affects Symbiosis and Exhibits a Calcium-Dependent Autocleavage Activity

2010 ◽  
Vol 23 (1) ◽  
pp. 124-129 ◽  
Author(s):  
Mandy Wenzel ◽  
Lars Friedrich ◽  
Michael Göttfert ◽  
Susanne Zehner
Keyword(s):  
Vigna Radiata ◽  
Physiological Role ◽  
Cleavage Sites ◽  
Wild Type ◽  
Type Iii ◽  
Calcium Dependent ◽  
Double Mutant Strain ◽  
Wild Type Phenotype ◽  
Domain Of Unknown Function

The type III–secreted proteins NopE1 and NopE2 of Bradyrhizobium japonicum contain a repeated domain of unknown function (DUF1521), which is present in a few uncharacterized proteins. A nopE1/nopE2 double mutant strain exhibited higher nodulation efficiency on Vigna radiata KPS2 than the wild type or single nopE1 or nopE2 mutants. This indicates that both proteins are effectors that functionally overlap. To test translocation into the plant cell compartment during symbiosis, NopE1 and NopE2 were fused with adenylate cyclase (cya) as reporter. A fusion with the full-length proteins or N-terminal peptides resulted in increased cAMP levels in nodules, indicating translocation. Purified NopE1 exhibited self-cleavage in the presence of Ca2+. Two identical cleavage sites (GD'PHVD) were identified inside the DUF1521 domains. The C-terminal cleavage site was analyzed by alanine scanning. Protein variants in which aspartate or proline next to the cleavage sites was substituted displayed no cleavage. A noncleavable protein was obtained by exchange of the aspartate residues preceding both cleavage sites. Complementation analysis with the noncleavable NopE1 variant did not restore wild-type phenotype on Vigna radiata KPS2, indicating a physiological role of NopE1 cleavage in effector function.

scholarly journals Biochemical Genetics of the Cryptic Gene System for Cellobiose Utilization in Escherichia coli K12

Genetics ◽  
1987 ◽  
Vol 115 (3) ◽  
pp. 419-429
Author(s):  
Maja Kricker ◽  
Barry G Hall
Keyword(s):  
Escherichia Coli ◽  
Microbial Evolution ◽  
Transport Protein ◽  
Wild Type ◽  
Phosphotransferase System ◽  
E Coli ◽  
Escherichia Coli K12 ◽  
Biochemical Assays ◽  
In The Wild

ABSTRACT The cellobiose catabolic system of Escherichia coli K12 is being used to study the role of cryptic genes in microbial evolution. Wild-type E. coli K12 do not utilize the β-glucoside sugars, arbutin, salicin and cellobiose. A Cel+ (cellobiose utilizing) mutant which grows on cellobiose, arbutin, and salicin was isolated previously from wild-type E. coli K12. Biochemical assays indicate that a cel structural gene (celT) specifies a single transport protein that is a β-glucoside specific enzyme of the phosphoenolpyruvate-dependent phosphotransferase system. The transport protein phosphorylates β-glucosides at the expense of phosphoenolpyruvate. A single phosphoglucosidase, specified by celH, hydrolyzes phosphorylated cellobiose, arbutin, and salicin. The genes of the cel system are expressed constitutively in the Cel+ mutant, whereas they are not expressed at a detectable level in the wild-type strain. The transport and hydrolase genes are simultaneously silenced or simultaneously expressed and thus constitute an operon. Cel+ strains which fail to utilize one or more β-glucosides express the transport system at a lower level than do Cel+ strains which grow on all three β-glucosides. Other strains inducibly express a gene which specifies transport of arbutin but not the other β-glucosides. The arbutin transport gene, arbT, maps outside of the cel locus.

Sign in / Sign up

Export Citation Format

Share Document