Subunit II (b') and Not Subunit I (b) of Photosynthetic ATP Synthases is Equivalent to Subunit b of the ATP Synthases from Nonphotosynthetic Eubacteria. Evidence for a New Assignment of b-Type F0 Subunits

1997 ◽  
Vol 52 (11-12) ◽  
pp. 789-798 ◽  
Author(s):  
Hans-Jürgen Tiburzy ◽  
Richard J. Berzborn
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Structural Feature ◽  
Atp Synthase ◽  
Primary Structure ◽  
Structural Features ◽  
Amino Acid Sequences ◽  
E Coli ◽  
Subunit B ◽  
Atp Synthases

Abstract Subunit I of chloroplast ATP synthase is reviewed until now to be equivalent to subunit b of Escherichia coli ATP synthase, whereas subunit II is suggested to be an additional subunit in photosynthetic ATP synthases lacking a counterpart in E. coli. After publication of some sequences of subunits II a revision of this assignment is necessary. Based on the analysis of 51 amino acid sequences of b-type subunits concerning similarities in primary structure, iso­electric point and a discovered discontinuous structural feature, our data provide evidence that chloroplast subunit II (subunit b' of photosynthetic eubacteria) and not chloroplast subunit I (subunit b of photosynthetic eubacteria) is the equivalent of subunit b of nonphoto­ synthetic eubacteria, and therefore does have a counterpart in e.g. E. coli. In consequence, structural features essential for function should be looked for on subunit II (b').

scholarly journals Roles of the C-Terminal Amino Acids of Non-Hexameric Helicases: Insights from Escherichia coli UvrD

2021 ◽  
Vol 22 (3) ◽  
pp. 1018
Author(s):  
Hiroaki Yokota
Keyword(s):  
Escherichia Coli ◽  
Amino Acids ◽  
Amino Acid ◽  
Single Molecule ◽  
Underlying Mechanism ◽  
Amino Acid Sequences ◽  
E Coli ◽  
X Ray Crystallography ◽  
Terminal Amino

Helicases are nucleic acid-unwinding enzymes that are involved in the maintenance of genome integrity. Several parts of the amino acid sequences of helicases are very similar, and these quite well-conserved amino acid sequences are termed “helicase motifs”. Previous studies by X-ray crystallography and single-molecule measurements have suggested a common underlying mechanism for their function. These studies indicate the role of the helicase motifs in unwinding nucleic acids. In contrast, the sequence and length of the C-terminal amino acids of helicases are highly variable. In this paper, I review past and recent studies that proposed helicase mechanisms and studies that investigated the roles of the C-terminal amino acids on helicase and dimerization activities, primarily on the non-hexermeric Escherichia coli (E. coli) UvrD helicase. Then, I center on my recent study of single-molecule direct visualization of a UvrD mutant lacking the C-terminal 40 amino acids (UvrDΔ40C) used in studies proposing the monomer helicase model. The study demonstrated that multiple UvrDΔ40C molecules jointly participated in DNA unwinding, presumably by forming an oligomer. Thus, the single-molecule observation addressed how the C-terminal amino acids affect the number of helicases bound to DNA, oligomerization, and unwinding activity, which can be applied to other helicases.

scholarly journals In silico analysis of virulence associated genes in genomes of Escherichia coli strains causing colibacillosis in poultry

2017 ◽  
Vol 61 (4) ◽  
pp. 421-426 ◽  
Author(s):  
Joanna Kołsut ◽  
Paulina Borówka ◽  
Błażej Marciniak ◽  
Ewelina Wójcik ◽  
Arkadiusz Wojtasik ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Virulence Factors ◽  
De Novo ◽  
Protein Sequences ◽  
In Silico Analysis ◽  
Amino Acid Sequences ◽  
Common Disease ◽  
Bacterial Genomes ◽  
E Coli

AbstractIntroduction: Colibacillosis – the most common disease of poultry, is caused mainly by avian pathogenic Escherichia coli (APEC). However, thus far, no pattern to the molecular basis of the pathogenicity of these bacteria has been established beyond dispute. In this study, genomes of APEC were investigated to ascribe importance and explore the distribution of 16 genes recognised as their virulence factors.Material and Methods: A total of 14 pathogenic for poultry E. coli strains were isolated, and their DNA was sequenced, assembled de novo, and annotated. Amino acid sequences from these bacteria and an additional 16 freely available APEC amino acid sequences were analysed with the DIFFIND tool to define their virulence factors.Results: The DIFFIND tool enabled quick, reliable, and convenient assessment of the differences between compared amino acid sequences from bacterial genomes. The presence of 16 protein sequences indicated as pathogenicity factors in poultry resulted in the generation of a heatmap which categorises genomes in terms of the existence and similarity of the analysed protein sequences.Conclusion: The proposed method of detection of virulence factors using the capabilities of the DIFFIND tool may be useful in the analysis of similarities of E. coli and other sequences deriving from bacteria. Phylogenetic analysis resulted in reliable segregation of 30 APEC strains into five main clusters containing various virulence associated genes (VAGs).

scholarly journals Characterization of human and mouse granulocyte-macrophage-colony-stimulating factors derived from Escherichia coli

1987 ◽  
Vol 247 (1) ◽  
pp. 195-199 ◽  
Author(s):  
J L Schrimsher ◽  
K Rose ◽  
M G Simona ◽  
P Wingfield
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Amino Acid Sequences ◽  
Natural Material ◽  
Animal Cells ◽  
Colony Stimulating Factors ◽  
E Coli ◽  
Macrophage Colony ◽  
The One ◽  
Human And Mouse

Human and mouse granulocyte-macrophage-colony-stimulating factors (hGM-CSF and mGM-CSF, respectively), isolated from Escherichia coli cells expressing the corresponding human and mouse genes, have been characterized. The observed properties of the proteins have been compared with those properties which can be deduced from the DNA sequence alone and the published properties of natural GM-CSFs. The purified E. coli-derived proteins were found to have the expected molecular masses, amino acid compositions and N- and C-terminal amino acid sequences. The finding of 70-90% unprocessed N-terminal methionine for both proteins is discussed. The four Cys residues were found to be involved in two intramolecular disulphide bonds, linking the first and third, and second and fourth Cys residues. This disulphide bond arrangement is probably the one existing in natural material, since, although not glycosylated, both E. coli-derived proteins showed biological activity (colony stimulating assay for hGM-CSF, and cell proliferation assay for mGM-CSF) comparable with that reported for the respective proteins purified from animal cells.

Expression and Regulation of the Arsenic Resistance Operon of Acidiphilium multivorum AIU 301 Plasmid pKW301 in Escherichia coli

1998 ◽  
Vol 64 (2) ◽  
pp. 411-418 ◽  
Author(s):  
Katsuhisa Suzuki ◽  
Norio Wakao ◽  
Tetsuya Kimura ◽  
Kazuo Sakka ◽  
Kunio Ohmiya
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Constitutive Expression ◽  
Amino Acid Sequences ◽  
Gene Products ◽  
Arsenic Resistance ◽  
E Coli ◽  
Molecular Weights ◽  
Rna Polymerase Promoter ◽  
Extension Analysis

ABSTRACT The arsenic resistance (ars) operon from plasmid pKW301 of Acidiphilium multivorum AIU 301 was cloned and sequenced. This DNA sequence contains five genes in the following order: arsR, arsD, arsA,arsB, arsC. The predicted amino acid sequences of all of the gene products are homologous to the amino acid sequences of the ars gene products of Escherichia coliplasmid R773 and IncN plasmid R46. The ars operon cloned from A. multivorum conferred resistance to arsenate and arsenite on E. coli. Expression of the arsgenes with the bacteriophage T7 RNA polymerase-promoter system allowedE. coli to overexpress ArsD, ArsA, and ArsC but not ArsR or ArsB. The apparent molecular weights of ArsD, ArsA, and ArsC were 13,000, 64,000, and 16,000, respectively. A primer extension analysis showed that the ars mRNA started at a position 19 nucleotides upstream from the arsR ATG in E. coli. Although the arsR gene of A. multivorum AIU 301 encodes a polypeptide of 84 amino acids that is smaller and less homologous than any of the other ArsR proteins, inactivation of the arsR gene resulted in constitutive expression of the ars genes, suggesting that ArsR of pKW301 controls the expression of this operon.

scholarly journals Characterization of a 12-Kilodalton Rhodanese Encoded byglpE of Escherichia coli and Its Interaction with Thioredoxin

2000 ◽  
Vol 182 (8) ◽  
pp. 2277-2284 ◽  
Author(s):  
W. Keith Ray ◽  
Gang Zeng ◽  
M. Benjamin Potters ◽  
Aqil M. Mansuri ◽  
Timothy J. Larson
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Amino Acid Sequence ◽  
Active Site ◽  
Amino Acid Sequences ◽  
E Coli ◽  
Active Site Cysteine ◽  
Clusters Of Orthologous Groups ◽  
Thioredoxin 1 ◽  
First Time

ABSTRACT Rhodaneses catalyze the transfer of the sulfane sulfur from thiosulfate or thiosulfonates to thiophilic acceptors such as cyanide and dithiols. In this work, we define for the first time the gene, and hence the amino acid sequence, of a 12-kDa rhodanese fromEscherichia coli. Well-characterized rhodaneses are comprised of two structurally similar ca. 15-kDa domains. Hence, it is thought that duplication of an ancestral rhodanese gene gave rise to the genes that encode the two-domain rhodaneses. The glpEgene, a member of the sn-glycerol 3-phosphate (glp) regulon of E. coli, encodes the 12-kDa rhodanese. As for other characterized rhodaneses, kinetic analysis revealed that catalysis by purified GlpE occurs by way of an enzyme-sulfur intermediate utilizing a double-displacement mechanism requiring an active-site cysteine. TheKm s for SSO3 2− and CN− were 78 and 17 mM, respectively. The apparent molecular mass of GlpE under nondenaturing conditions was 22.5 kDa, indicating that GlpE functions as a dimer. GlpE exhibited ak cat of 230 s−1. Thioredoxin 1 from E. coli, a small multifunctional dithiol protein, served as a sulfur acceptor substrate for GlpE with an apparentKm of 34 μM when thiosulfate was near itsKm , suggesting that thioredoxin 1 or related dithiol proteins could be physiological substrates for sulfurtransferases. The overall degree of amino acid sequence identity between GlpE and the active-site domain of mammalian rhodaneses is limited (∼17%). This work is significant because it begins to reveal the variation in amino acid sequences present in the sulfurtransferases. GlpE is the first among the 41 proteins in COG0607 (rhodanese-related sulfurtransferases) of the database Clusters of Orthologous Groups of proteins (http://www.ncbi.nlm.nih.gov/COG/ ) for which sulfurtransferase activity has been confirmed.

Immunogenic peptide mimotopes from an epitope of Escherichia coli O157 LPS

2016 ◽  
Vol 473 (21) ◽  
pp. 3791-3804 ◽  
Author(s):  
Armando Navarro ◽  
Ulises Hernández-Chiñas ◽  
Delia Licona-Moreno ◽  
Edgar Zenteno ◽  
Alejandro Cravioto ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Amino Acid Sequences ◽  
Escherichia Coli O157 ◽  
Serum Samples ◽  
Haemolytic Uremic Syndrome ◽  
E Coli ◽  
Positive Reactivity ◽  
Peptide Mimotopes ◽  
Uremic Syndrome

Escherichia coli O157:H7 is a subtype of Shiga toxin-producing E. coli that is associated with haemorrhagic colitis and haemolytic uremic syndrome (HUS). Studies of populations in endemic areas have reported that the presence of specific antibodies against the O157 lipopolysaccharide (LPS) is associated with a lower incidence of diarrhoea and HUS. Phage display and IgG anti-O157 LPS antibodies were used in the present study to select peptide mimotopes of O157 LPS expressed in protein III of the M13 phage. Synthetic peptides (SP) were designed using the derived amino acid sequences obtained from DNA nucleotides of 63 selected phagotopes. The LxP/YP/SxL motif was identified in five of the phagotope amino acid sequences. Antibody responses against the phagotopes and their corresponding SPs were evaluated. SP12, one of the designed SP, induced the production of antibodies against the homologous peptide (1:800) and O157 LPS (1:200). The specificity of anti-SP12 antiserum was confirmed by analyzing its response to SP3, an SP with a different amino acid sequence than that of SP12, as well as against an E. coli LPS different from O157. Competitive studies with SP12 and O157 LPS showed a significant decrease in anti-SP12 and anti-LPS O157 antiserum responses against SP12 and O157 LPS, respectively. Eighteen (82%) of the 22 human serum samples with positive reactivity against E. coli O157 LPS reacted with SP12 SP (cut-off >0.4). These results support the idea that SP12 is an immunogenic mimotope of O157 LPS.

Cloning and Sequencing of the Histidine Decarboxylase Gene from Photobacterium phosphoreum and its Functional Expression in Escherichia coli

2006 ◽  
Vol 69 (8) ◽  
pp. 1768-1776 ◽  
Author(s):  
HIDEAKI MORII ◽  
KENTARO KASAMA ◽  
RAUL HERRERA-ESPINOZA
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Histidine Decarboxylase ◽  
Halophilic Bacteria ◽  
Trna Synthetase ◽  
Amino Acid Sequences ◽  
Photobacterium Phosphoreum ◽  
Bootstrap Support ◽  
Amino Acid Permease ◽  
E Coli

The major causative agent of scombroid poisoning is histamine formed by bacterial decarboxylation of histidine. We reported previously that histamine was exclusively formed by the psychrotrophic halophilic bacteria Photobacterium phosphoreum in scombroid fish during storage at or below 10°C. Moreover, histamine-forming ability was affected by two histidine decarboxylases (HDCs): constitutive and inducible enzymes. In this study, the gene encoding P. phosphoreum HDC was cloned into Escherichia coli and sequenced. A sequence analysis of the DNA corresponding to the hdc gene revealed an open reading frame of 1,140 bp coding for a pyridoxal-5′-phosphate-dependent HDC of 380 amino acid residues with a predicted molecular mass of 42.6 kDa. The HDC amino acid sequences formed a phylogenetic clade with strong bootstrap support and revealed high sequence similarities among the P. phosphoreum isolate and species of the family Enterobacteriaceae and a separate phylogenetic branch with the lowest sequence similarity between the isolate and the taxonomically closer Listonella anguillarum. The T7 promoter was used to overexpress the hdc gene in E. coli cells. The recombinant clone, E. coli BL21(DE3), displayed significant levels of HDC activity. The recombinant hdc gene was suggested to code the inducible HDC; therefore, the optimum reaction conditions of the recombinant HDC were similar to those of the inducible HDC in the P. phosphoreum isolate. In addition, a putative catabolite-repressor protein binding site, amino acid permease gene, and histidine-tRNA synthetase gene were found in flanking regions of the hdc gene.

scholarly journals Reconstruction and optimized expression of a synthetic secretory leukocyte protease inhibitor (SLPI) gene in Escherichia coli BL21

2020 ◽  
Author(s):  
Mudyawati Kamaruddin
Keyword(s):  
Escherichia Coli ◽  
Wound Healing ◽  
Amino Acid ◽  
Fusion Protein ◽  
Amino Acid Sequences ◽  
E Coli ◽  
Usage Frequency ◽  
Sds Page ◽  
Double Digestion ◽  
Encoding Genes

An active substance that has the greatest effect on wound healing is Secretory Leukocyte ProteaseInhibitor (SLPI). It is known that the SLPI encoding genes can be isolated and expressed onamnion membrane. Previous studies, we isolated and optimized the SLPI gene throughEscherichia coli BL21 (DE3) mediated pET101/DTOPO, which expressed active recombinanthuman SLPI (rhSLPI ) stored in pET-ESLPI. However, the expression of the rhSLPI products hasnot yet been accomplished. In this study, we optimized SLPI expression by developing a syntheticSLPI gene based on amino acid sequences with codons and expressed in E. coli BL21 to give themaximum expression. We used pUC57 and pET-32a plasmids to promote the cloning of syntheticSLPI genes. A codon-optimized SLPI gene was successfully synthesized with codon adaptationindex value showing the distribution of codon usage frequency along the length of the genesequence. In addition, the pET-SLPIopt fusion protein was successfully optimized with band sizesof 5900bp (pET-32a) and 413bp (SLPI) by double-digestion of NcoI and EcoI restriction enzymes.After the pET-SLPIopt was induced with various IPTG concentrations (50, 100 and 500 uM) at30°C, both soluble and insoluble fractions were analyzed as a result of SDS-PAGE which showedthat the fusion protein, expressed predominantly in the supernatant, was 29.18 kDa. Our reportedfindings the recombinant protein of SLPI through pET-32a plasmid could be expressed indissolved form.

A comparison of the citrate synthases of Escherichia coli and Acinetobacter anitratum

1980 ◽  
Vol 58 (9) ◽  
pp. 696-706 ◽  
Author(s):  
David Morse ◽  
Harry W. Duckworth
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Citrate Synthase ◽  
Amino Acid Sequences ◽  
Aerobic Bacterium ◽  
Acetyl Coa ◽  
Gram Negative ◽  
E Coli ◽  
Sulfhydryl Reagent ◽  
Complete Inactivation

Citrate synthase has been purified to homogeneity from a strain of the Gram-negative aerobic bacterium Acinetobacter anitratum in a form which retains its sensitivity to the allosteric inhibitor NADH. In subunit size, amino acid composition, and antigenic reactivity the enzyme shows a marked structural resemblance to the citrate synthase of the Gram-negative facultative anaerobe Escherichia coli. Whereas the E. coli enzyme is subject to a strong, hyperbolic inhibition by NADH (Hill's number n = 1.0, K1 = 2 μM), the A. anitratum enzyme shows a weak, sigmoid response (n = 1.6, I0.5 = 140 μM) to this nucleotide. With E. coli, NADH inhibition is competitive with acetyl-CoA, and noncompetitive with oxaloacetate; with A. anitratum, NADH is noncompetitive with both substrates. Acinetobacter anitratum citrate synthase shows hyperbolic saturation with acetyl-CoA (n = 1.8). The finding of Weitzman and Jones (Nature (London) 219, 270 (1968)) that NADH inhibition of the enzyme from Acinetobacter spp. is reversible by AMP, while that from E. coli is not, is explained by the much greater affinity of the E. coli enzyme for NADH. Unlike E. coli citrate synthase, the A. anitratum enzyme does not react with the sulfhydryl reagent 5,5′-dithiobis(2-nitrobenzoic acid) (DTNB) in the absence of denaturation. With a second sulfhydryl reagent, 4,4′-dithiodipyridine (4,4′-PDS), the A. anitratum enzyme reacts with 1 equiv. of subunit; this modification induces a partial activity loss (attributable to a rise in the Km for acetyl-CoA) and an increase in the sensitivity to NADH. With the E. coli enzyme, 4,4′-PDS causes complete inactivation. Acinetobacter anitratum citrate synthase is much more resistant to urea denaturation than the E. coli enzyme is; the resistance of both enzymes to urea is greatly improved in the presence of 1 M KCl. It is suggested that the amino acid sequences of the subunits of the citrate synthases of these two bacteria are about 90% homologous, and that the 10% differences are in key residues, perhaps largely in the subunit contact regions, which account for the differences in allosteric properties.

Sign in / Sign up

Export Citation Format

Share Document