Antigenic Relatedness and Partial Amino Acid Sequences of Pili of Escherichia coli Serotypes O1, O2, and O78 Pathogenic to Poultry

1987 ◽  
Vol 31 (4) ◽  
pp. 809 ◽  
Author(s):  
A. Suwanichkul ◽  
B. Panigrahy ◽  
R. M. Wagner
2021 ◽  
Vol 22 (3) ◽  
pp. 1018
Author(s):  
Hiroaki Yokota

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.


2002 ◽  
Vol 76 (11) ◽  
pp. 5829-5834 ◽  
Author(s):  
Yoshio Mori ◽  
Mohammed Ali Borgan ◽  
Naoto Ito ◽  
Makoto Sugiyama ◽  
Nobuyuki Minamoto

ABSTRACT Avian rotavirus NSP4 glycoproteins expressed in Escherichia coli acted as enterotoxins in suckling mice, as did mammalian rotavirus NSP4 glycoproteins, despite great differences in the amino acid sequences. The enterotoxin domain of PO-13 NSP4 exists in amino acid residues 109 to 135, a region similar to that reported in SA11 NSP4.


2001 ◽  
Vol 67 (4) ◽  
pp. 1601-1606 ◽  
Author(s):  
Mitsunori Ishiguro ◽  
Satoshi Kaneko ◽  
Atsushi Kuno ◽  
Yoshinori Koyama ◽  
Shigeki Yoshida ◽  
...  

ABSTRACT The nucleotide sequence of the Thermus sp. strain T2 DNA coding for a thermostable α-galactosidase was determined. The deduced amino acid sequence of the enzyme predicts a polypeptide of 474 amino acids (M r, 53,514). The observed homology between the deduced amino acid sequences of the enzyme and α-galactosidase from Thermus brockianus was over 70%.Thermus sp. strain T2 α-galactosidase was expressed in its active form in Escherichia coli and purified. Native polyacrylamide gel electrophoresis and gel filtration chromatography data suggest that the enzyme is octameric. The enzyme was most active at 75°C forp-nitrophenyl-α-d-galactopyranoside hydrolysis, and it retained 50% of its initial activity after 1 h of incubation at 70°C. The enzyme was extremely stable over a broad range of pH (pH 6 to 13) after treatment at 40°C for 1 h. The enzyme acted on the terminal α-galactosyl residue, not on the side chain residue, of the galactomanno-oligosaccharides as well as those of yeasts and Mortierella vinacea α-galactosidase I. The enzyme has only one Cys residue in the molecule.para-Chloromercuribenzoic acid completely inhibited the enzyme but did not affect the mutant enzyme which contained Ala instead of Cys, indicating that this Cys residue is not responsible for its catalytic function.


1997 ◽  
Vol 52 (11-12) ◽  
pp. 789-798 ◽  
Author(s):  
Hans-Jürgen Tiburzy ◽  
Richard J. Berzborn

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').


2006 ◽  
Vol 34 (1) ◽  
pp. 143-145 ◽  
Author(s):  
T.A. Clarke ◽  
A.M. Hemmings ◽  
B. Burlat ◽  
J.N. Butt ◽  
J.A. Cole ◽  
...  

The recent crystallographic characterization of NrfAs from Sulfurospirillum deleyianum, Wolinella succinogenes, Escherichia coli and Desulfovibrio desulfuricans allows structurally conserved regions to be identified. Comparison of nitrite and sulphite reductase activities from different bacteria shows that the relative activities vary according to organism. By comparison of both amino acid sequences and structures, differences can be identified in the monomer–monomer interface and the active-site channel; these differences could be responsible for the observed variance in substrate activity and indicate that subtle changes in the NrfA structure may optimize the enzyme for different roles.


1980 ◽  
Vol 103 (3) ◽  
pp. 456-461
Author(s):  
B. Laine ◽  
D. Kmiecik ◽  
P. Sautiere ◽  
G. Biserte ◽  
M. Cohen-Solal

2000 ◽  
Vol 62 (9) ◽  
pp. 941-945 ◽  
Author(s):  
Yoshitsugu OCHIAI ◽  
Hideto FUKUSHI ◽  
Cai YAN ◽  
Tsuyoshi YAMAGUCHI ◽  
Katsuya HIRAI

2017 ◽  
Vol 61 (4) ◽  
pp. 421-426 ◽  
Author(s):  
Joanna Kołsut ◽  
Paulina Borówka ◽  
Błażej Marciniak ◽  
Ewelina Wójcik ◽  
Arkadiusz Wojtasik ◽  
...  

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).


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