scholarly journals Clostridium symbiosum

2020 ◽  
Author(s):  
Keyword(s):  
Clostridium Symbiosum

scholarly journals Molecular and Low-Resolution Structural Characterization of the Na+-Translocating Glutaconyl-CoA Decarboxylase From Clostridium symbiosum

2020 ◽  
Vol 11 ◽  
Author(s):  
Stella Vitt ◽  
Simone Prinz ◽  
Nils Hellwig ◽  
Nina Morgner ◽  
Ulrich Ermler ◽  
...  
Keyword(s):  
Structural Characterization ◽  
Low Resolution ◽  
Clostridium Symbiosum

Allosteric behaviour of 1:5 hybrids of mutant subunits of Clostridium symbiosum glutamate dehydrogenase differing in their amino acid specificity

2001 ◽  
Vol 360 (3) ◽  
pp. 651-656 ◽  
Author(s):  
Arun GOYAL ◽  
Xing-Guo WANG ◽  
Paul C. ENGEL
Keyword(s):  
Amino Acid ◽  
Glutamate Dehydrogenase ◽  
Cysteine Residue ◽  
The Other ◽  
Wild Type Enzyme ◽  
Triple Mutant ◽  
Subunit Stoichiometry ◽  
Clostridium Symbiosum ◽  
Mutant Forms ◽  
Fold Activation

Hybrid hexamers were made by refolding mixtures of two mutant forms of clostridial glutamate dehydrogenase. Mutant Cys320Ser (C320S) has a similar activity to the wild-type enzyme, but is unreactive with Ellman's reagent, 5,5′-dithiobis(2-nitrobenzoate) (DTNB). The triple mutant Lys89Leu/Ala163Gly/Ser380Ala (K89L/A163G/S380A), active with norleucine but not glutamate, is inactivated by DTNB, since the amino acid residue at position 320 is a cysteine residue. The chosen ratio favoured 1:5 hybrids of the triple mutant and C320S. The renatured mixture was treated with DTNB and separated on an NAD+–agarose column to which only C320S subunits bind tightly. Fractions were monitored for glutamate and norleucine activity and for releasable thionitrobenzoate to establish subunit stoichiometry. A fraction highly enriched in the 1:5 hybrid was identified. Homohexamers (C320S with 40mM glutamate and 1mM NAD+ at pH8.8, or K89L/A163G/S380A with 70mM norleucine and 1mM NAD+ at pH8.5) showed allosteric activation; succinate activated C320S approx. 50-fold (EC50 = 70mM, h = 2.4), and glutarate gave approx. 30-fold activation (EC50 = 35mM, h = 2.3). For the triple mutant, corresponding values were 80mM and 2.2 for succinate, and 75mM and 1.7 for glutarate, but maximal activation was only about 2-fold. In the 1:5 hybrid, with only one norleucine-active subunit per hexamer, responses to glutarate and succinate were still co-operative, and activation was more extensive than in the triple mutant homohexamer. A single norleucine-active subunit can thus respond co-operatively to a substrate analogue at the other five inactive sites. On the other hand, similar hyperbolic dependence on the norleucine concentration for the hybrid and the triple mutant homohexamer reflected the inability of C320S subunits to bind norleucine. With glutamate at pH8.8, an h value of 3.6 was obtained for the 1:5 hybrid, in contrast with an h value of 5.2 for the C320S homohexamer. The ‘foreign’ subunit evidently impedes inter-subunit communication to some extent.

scholarly journals Characterization of the surface layer glycoprotein of Clostridium symbiosum HB25.

1990 ◽  
Vol 172 (5) ◽  
pp. 2576-2583 ◽  
Author(s):  
P Messner ◽  
K Bock ◽  
R Christian ◽  
G Schulz ◽  
U B Sleytr
Keyword(s):  
Surface Layer ◽  
Clostridium Symbiosum

scholarly journals Fecal Clostridium symbiosum for Noninvasive Detection of Early and Advanced Colorectal Cancer: Test and Validation Studies

EBioMedicine ◽  
2017 ◽  
Vol 25 ◽  
pp. 32-40 ◽  
Author(s):  
Yuan-Hong Xie ◽  
Qin-Yan Gao ◽  
Guo-Xiang Cai ◽  
Xiao-Ming Sun ◽  
Tian-Hui Zou ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Validation Studies ◽  
Advanced Colorectal Cancer ◽  
Noninvasive Detection ◽  
Clostridium Symbiosum

scholarly journals Crystal structure of a chimaeric bacterial glutamate dehydrogenase

2016 ◽  
Vol 72 (6) ◽  
pp. 462-466 ◽  
Author(s):  
Tânia Oliveira ◽  
Michael A. Sharkey ◽  
Paul C. Engel ◽  
Amir R. Khan
Keyword(s):  
Crystal Structure ◽  
Glutamate Dehydrogenase ◽  
Rigid Bodies ◽  
Nucleotide Binding Domain ◽  
Oxidative Deamination ◽  
E Coli ◽  
Cofactor Binding ◽  
Signature Sequences ◽  
Clostridium Symbiosum ◽  
Domain I

Glutamate dehydrogenases (EC 1.4.1.2–4) catalyse the oxidative deamination of L-glutamate to α-ketoglutarate using NAD(P)+as a cofactor. The bacterial enzymes are hexameric, arranged with 32 symmetry, and each polypeptide consists of an N-terminal substrate-binding segment (domain I) followed by a C-terminal cofactor-binding segment (domain II). The catalytic reaction takes place in the cleft formed at the junction of the two domains. Distinct signature sequences in the nucleotide-binding domain have been linked to the binding of NAD+versusNADP+, but they are not unambiguous predictors of cofactor preference. In the absence of substrate, the two domains move apart as rigid bodies, as shown by the apo structure of glutamate dehydrogenase fromClostridium symbiosum. Here, the crystal structure of a chimaeric clostridial/Escherichia colienzyme has been determined in the apo state. The enzyme is fully functional and reveals possible determinants of interdomain flexibility at a hinge region following the pivot helix. The enzyme retains the preference for NADP+cofactor from the parentE. colidomain II, although there are subtle differences in catalytic activity.

scholarly journals Transfer of Vancomycin Resistance Transposon Tn1549 from Clostridium symbiosum to Enterococcus spp. in the Gut of Gnotobiotic Mice

2006 ◽  
Vol 50 (3) ◽  
pp. 1054-1062 ◽  
Author(s):  
Aline Launay ◽  
Susan A. Ballard ◽  
Paul D. R. Johnson ◽  
M. Lindsay Grayson ◽  
Thierry Lambert
Keyword(s):  
Hot Spots ◽  
Low Frequency ◽  
Vancomycin Resistance ◽  
Conjugative Transposons ◽  
Target Dna ◽  
Enterococcus Spp ◽  
Clostridium Symbiosum ◽  
Gnotobiotic Mice ◽  
Flanking Regions

ABSTRACT The vancomycin resistance vanB2 gene cluster is disseminated worldwide and has been found in phylogenetically remote bacterial genera. The vanB2 operon is part of conjugative transposons Tn1549/Tn5382, but conjugative transposition of these elements has not been demonstrated. We have obtained transfer of a Tn1549-like element (referred to herein as “Tn1549-like”) from Clostridium symbiosum MLG101 to Enterococcus faecium 64/3 and Enterococcus faecalis JH2-2 in the digestive tract of gnotobiotic mice and to E. faecium 64/3 in vitro. Retransfer of Tn1549-like from an E. faecium transconjugant also containing Tn916 to E. faecium BM77 was obtained in vitro, albeit at a very low frequency. Transfer efficiency was found to be both donor and recipient dependent. Pulsed-field gel electrophoresis analysis of total SmaI-digested DNA of 48 transconjugants indicated in 27 instances the acquisition of ca. 34 kb of DNA. Two transconjugants harbored two copies of the transposon. Sequencing of the flanking regions of Tn1549-like in 48 transconjugants revealed 29 integration events in 26 loci in the E. faecium genome, and two hot spots for insertion were identified. Integration of the transposon was associated with the acquisition of 5 (n = 18) or 6 (n = 7) bp of donor DNA or with 5-bp duplications of target DNA in the remaining transconjugants. These data demonstrate functionality of the Tn1549-like element and attest that the transfer of the vanB operon between enterococci and human commensal anaerobes occurs in the intestinal environment.

Clostridium vitabionis sp. nov., isolated from the large intestine of a mini-pig

2019 ◽  
Vol 71 (3) ◽  
Author(s):  
Yeseul Shin ◽  
Jayoung Paek ◽  
Hongik Kim ◽  
Joong-Ki Kook ◽  
Young Hyo Chang
Keyword(s):  
Large Intestine ◽  
Type Species ◽  
Sequence Similarity ◽  
Diaminopimelic Acid ◽  
Minor Amount ◽  
Rrna Gene ◽  
Content Type ◽  
Link Type ◽  
Clostridium Symbiosum ◽  
A Minor

An obligately anaerobic, Gram-stain-negative, spore-forming, short rod-shaped bacterium, designated strain YH- T4B42T, was isolated from the large intestine of a mini-pig. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belongs to the genus Clostridium and is most closely related to Clostridium aminophilum KCTC 5424T, Clostridium symbiosum KCTC 15329T and Clostridium butyricum KCTC 1871T, with 95.5, 92.4 and 83.0 % sequence similarity, respectively. The average nucleotide identity values for strain YH-T4B42T and the closest related strains were lower than 72 %. The G+C content of the isolate was 55.8 mol%. The cell-wall peptidoglycan was A1γ type and contained meso-diaminopimelic acid. The predominant fatty acids were C16 : 0, C18 : 1 cis 9, C14 : 0 and C18 : 0. The major end products of glucose fermentation were lactate, formate and acetate, with a minor amount of butyrate. Based on its phenotypic, phylogenetic and chemotaxonomic properties, a novel species, Clostridium vitabionis sp. nov., is proposed for strain YH-T4B42T (=KCTC 25105T=NBRC 114767T).

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