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991.
Alain Labbé Jorge G. Ganopolsky Christopher J. Martoni Satya Prakash Mitchell L. Jones 《PloS one》2014,9(12)
We performed an analysis to determine the importance of bile acid modification genes in the gut microbiome of inflammatory bowel disease and type 2 diabetic patients. We used publicly available metagenomic datasets from the Human Microbiome Project and the MetaHIT consortium, and determined the abundance of bile salt hydrolase gene (bsh), 7 alpha-dehydroxylase gene (adh) and 7-alpha hydroxysteroid dehydrogenase gene (hsdh) in fecal bacteria in diseased populations of Crohn''s disease (CD), Ulcerative Colitis (UC) and Type 2 diabetes mellitus (T2DM). Phylum level abundance analysis showed a significant reduction in Firmicute-derived bsh in UC and T2DM patients but not in CD patients, relative to healthy controls. Reduction of adh and hsdh genes was also seen in UC and T2DM patients, while an increase was observed in the CD population as compared to healthy controls. A further analysis of the bsh genes showed significant differences in the correlations of certain Firmicutes families with disease or healthy populations. From this observation we proceeded to analyse BSH protein sequences and identified BSH proteins clusters representing the most abundant strains in our analysis of Firmicute bsh genes. The abundance of the bsh genes corresponding to one of these protein clusters was significantly reduced in all disease states relative to healthy controls. This cluster includes bsh genes derived from Lachospiraceae, Clostridiaceae, Erysipelotrichaceae and Ruminococcaceae families. This metagenomic analysis provides evidence of the importance of bile acid modifying enzymes in health and disease. It further highlights the importance of identifying gene and protein clusters, as the same gene may be associated with health or disease, depending on the strains expressing the enzyme, and differences in the enzymes themselves. 相似文献
992.
Wei-Ling Lin Shih-Yun Guu Chan-Chuan Tsai Ekambaranellore Prakash Mohan Viswaraman Hsing-Bao Chen Chuan-Fa Chang 《PloS one》2015,10(6)
Molecules derived from cinnamon have demonstrated diverse pharmacological activities against infectious pathogens, diabetes and inflammatory diseases. This study aims to evaluate the effect of the cinnamon-derived molecule IND02 on the adhesion of leukocytes to host cells. The anti-inflammatory ability of IND02, a pentameric procyanidin type A polyphenol polymer isolated from cinnamon alcohol extract, was examined. Pretreatment with IND02 significantly reduced the attachment of THP-1 cells or neutrophils to TNF-α-activated HUVECs or E-selectin/ICAM-1, respectively. IND02 also reduced the binding of E-, L- and P-selectins with sialosides. Furthermore, IND02 could agglutinate human red blood cells (RBC), and the agglutination could be disrupted by sialylated glycoprotein. Our findings demonstrate that IND02, a cinnamon-derived compound, can interact with sialosides and block the binding of selectins and leukocytes with sialic acids. 相似文献
993.
Bhanumati Singh Vinay S. Chauhan Surendra Singh Prakash S. Bisen 《Current microbiology》2001,43(4):265-270
We propose a model to describe the changes taking place in biochemical processes/events to explain the development of heterocyst
and nitrogenase in a diazotrophic cyanobacterium Anabaena variabilis. For this purpose, a mutant strain of A. variabilis lacking heterocyst differentiation and incapable of growth with dinitrogen as the sole source of nitrogen has been isolated
after nitrosoguanidine (NTG) mutagenesis and selection by penicillin enrichment. The mutant strain (Het− Fix−) thus isolated has morphological variation and was incapable of reducing acetylene under anaerobic conditions, indicating
its mutational loss of the process of nitrogen fixation. The Het− Fix− mutant strain had reduced glutamine synthetase (transferase) activity compared with its wild-type counterpart, suggesting
a link between nif gene expression and the expression of gln A, the structural gene of GS. The Het− Fix− mutant strain compared with its wild-type strain also had an extremely high level of phycobiliprotein and a low level of
carotenoids. Furthermore, the coiling of vegetative filaments in the Het− Fix− mutant strain, which reduced the surface area to be exposed to light, was a direct indication of the chromatic adaptation,
because the mutant strain was found to be photosensitive, showing bleaching of the cells under high light intensity.
Received: 13 December 2000 / Accepted: 9 February 2001 相似文献
994.
Stefan Salzbrunn Golam Rasul G. K. Surya Prakash George A. Olah 《Journal of molecular modeling》2000,6(2):213-216
Structures and energies of XH4
+ and XH6
+ (X = B, Al and Ga) have been calculated at the density functional theory (DFT) B3LYP/6-311++G(3df,2pd) level. Calculations indicate that although the structure with a three center two electron (3c-2e) bond is the global minimum for BH4
+, the global minima of AlH4
+ and GaH4
+ are not those with one 3c-2e bond, but those with two 3c-2e bonds. For calibration, both structures of AlH4
+ were also calculated at the ab initio CCSD(T)/cc-pVTZ level and results in agreement with the DFT results were found. Similar calculations also indicate that although the C2v symmetrical structure with two 3c-2e bonds is the global minimum for BH6
+, the global minima of AlH6
+ and GaH6
+ are not the C2v symmetrical structures with two 3c-2e bonds but the C2 symmetrical structures with three 3c-2e bonds.Electronic Supplementary Material available. 相似文献
995.
We review the status of the two currently recognized subspecies of Lesser Spotted Eagle Aquila p. pomarina (western Eurasia) and A. p. hastata (Indian subcontinent) on the basis of museum diagnosis and field observations. We present differences between these two allopatric taxa which demonstrate that they should be treated as distinct species. Specifically, we present evidence of differences in plumage (both for adults and juveniles), external morphology, osteology, clutch size and behaviour. Particular emphasis is placed on differences in gape size and general cranial structure. 相似文献
996.
Felipe Samaniego Daniel Young Cara Grimes Vanessa Prospero Melpo Christofidou-Solomidou Horace M DeLisser Om Prakash Aysegul A Sahin Suizhao Wang 《Cell growth & differentiation》2002,13(8):387-395
Human cancer cells often produce tumors in animal models that incompletely reproduce the histology of the parental tumor. Kaposi's sarcoma (KS) cells, in particular, have not produced durable angiogenic lesions in animal models that resemble those of KS in humans. We investigated the contribution of transformed KS cells, vascular endothelial growth factor (VEGF), and human skin tissue on tumor development in a human skin graft/mouse model. High levels of serum VEGF (322 pg/ml) were seen in HIV-1-infected persons with KS compared with HIV-1-infected persons without KS (115 pg/ml). Human KS lesions expressed VEGF in the spindle cells. Transformed KS cells expressed the mitogenically active 121-amino acid and 165-amino acid isoforms of VEGF. Tumors induced by KS cells implanted in the SCID mice grew preferentially in human skin grafts rather than in ungrafted murine skin. Tumors induced in the presence of human skin grafts developed numerous lumens expressing alpha(v)beta(3) integrin. KS cells inoculated with neutralizing anti-VEGF antibody did not form tumors. This study supports an important role for VEGF in tumor development and shows how a human tissue can preferentially promote tumor growth. 相似文献
997.
The Saccharomyces cerevisiae DNA repair gene RAD23 encodes a nuclear protein containing a ubiquitin-like domain required for biological function. 总被引:11,自引:2,他引:9
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In eukaryotes, the posttranslational conjugation of ubiquitin to various cellular proteins marks them for degradation. Interestingly, several proteins have been reported to contain ubiquitin-like (ub-like) domains that are in fact specified by the DNA coding sequences of the proteins. The biological role of the ub-like domain in these proteins is not known; however, it has been proposed that this domain functions as a degradation signal rendering the proteins unstable. Here, we report that the product of the Saccharomyces cerevisiae RAD23 gene, which is involved in excision repair of UV-damaged DNA, bears a ub-like domain at its amino terminus. This finding has presented an opportunity to define the functional significance of this domain. We show that deletion of the ub-like domain impairs the DNA repair function of RAD23 and that this domain can be functionally substituted by the authentic ubiquitin sequence. Surprisingly, RAD23 is highly stable, and the studies reported herein indicate that its ub-like domain does not mediate protein degradation. Thus, in RAD23 at least, the ub-like domain affects protein function in a nonproteolytic manner. 相似文献
998.
Muhammad Asim Javed Arne Schwelm Nazanin Zamani-Noor Rasha Salih Marina Silvestre Vañó Jiaxu Wu Melaine González García Thies Marten Heick Chaoyu Luo Priyavashini Prakash Edel Pérez-López 《Molecular Plant Pathology》2023,24(2):89-106
Background
Plasmodiophora brassicae is the causal agent of clubroot disease of cruciferous plants and one of the biggest threats to the rapeseed (Brassica napus) and brassica vegetable industry worldwide.Disease symptoms
In the advanced stages of clubroot disease wilting, stunting, yellowing, and redness are visible in the shoots. However, the typical symptoms of the disease are the presence of club-shaped galls in the roots of susceptible hosts that block the absorption of water and nutrients.Host range
Members of the family Brassicaceae are the primary host of the pathogen, although some members of the family, such as Bunias orientalis, Coronopus squamatus, and Raphanus sativus, have been identified as being consistently resistant to P. brassicae isolates with variable virulence profile.Taxonomy
Class: Phytomyxea; Order: Plasmodiophorales; Family: Plasmodiophoraceae; Genus: Plasmodiophora; Species: Plasmodiophora brassicae (Woronin, 1877).Distribution
Clubroot disease is spread worldwide, with reports from all continents except Antarctica. To date, clubroot disease has been reported in more than 80 countries.Pathotyping
Based on its virulence on different hosts, P. brassicae is classified into pathotypes or races. Five main pathotyping systems have been developed to understand the relationship between P. brassicae and its hosts. Nowadays, the Canadian clubroot differential is extensively used in Canada and has so far identified 36 different pathotypes based on the response of a set of 13 hosts.Effectors and resistance
After the identification and characterization of the clubroot pathogen SABATH-type methyltransferase PbBSMT, several other effectors have been characterized. However, no avirulence gene is known, hindering the functional characterization of the five intercellular nucleotide-binding (NB) site leucine-rich-repeat (LRR) receptors (NLRs) clubroot resistance genes validated to date.Important Link
Canola Council of Canada is constantly updating information about clubroot and P. brassicae as part of their Canola Encyclopedia: https://www.canolacouncil.org/canola-encyclopedia/diseases/clubroot/ .Phytosanitary categorization
PLADBR: EPPO A2 list; Annex designation 9E. 相似文献999.
Yeast open reading frame YCR14C encodes a DNA beta-polymerase-like enzyme. 总被引:8,自引:3,他引:5
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R Prasad S G Widen R K Singhal J Watkins L Prakash S H Wilson 《Nucleic acids research》1993,21(23):5301-5307
We have shown by activity gel that overexpression in E. coli of a yeast chromosome 3 open reading frame (ORF) designated YCR14C and bearing homology to mammalian DNA polymerases beta results in a new DNA polymerase in the host cells. The molecular mass of this enzyme corresponded to the YCR14C-predicted 67 kDa protein, and NH2-terminal amino acid sequencing confirmed that the expressed protein was encoded by the yeast ORF. This new yeast DNA polymerase was purified to homogeneity from E.coli. In a fashion similar to that of mammalian beta-polymerases, the purified yeast enzyme exhibited distributive DNA synthesis on DNA substrate with a single-stranded template and processive gap-filling synthesis on a short-gapped DNA substrate. Activity of this yeast beta-polymerase-like enzyme was sensitive to the beta-polymerase inhibitor ddNTP and resistant to both 1 mM NEM and neutralizing antibody to E. coli DNA polymerase I. These results, therefore, indicate that YCR14C encodes a DNA beta-polymerase-like enzyme in yeast, and we name it DNA polymerase IV. Yeast strains harboring a deletion mutation of the pol IV gene are viable, they exhibit no increase in sensitivity to ultraviolet light, ionizing radiation or alkylating agents, and sporulation and spore viability are not affected in the mutant. 相似文献
1000.
Extensin, a hydroxyproline-rich glycoprotein comprising substantial amounts of -l-arabinose-hydroxyproline glycosidic linkages is believed to be insolubilized in the cell wall during host-pathogen interaction by a peroxidase/hydroperoxide-mediated cross-linking process. Both extensin precursor and extensin peroxidase were ionically eluted from intact water-washed tomato (hybrid) of Lycopersicon esculentum Mill. and L. peruvianum L. (Mill.) cells in suspension cultures and purified to homogeneity by a rapid and simple procedure under mild and non-destructive experimental conditions. The molecular weight of native extensin precursor was estimated to be greater than 240–300 kDa by Superose-12 gel-filtration chromatography. Extensin monomers have previously been designated a molecular weight of approximately 80 kDa. Our results indicate that salt-eluted extensin precursor is not monomeric. Agarose-gel electrophoresis, Superose-12-gel-filtration, extensin-peroxidase-catalysed cross-linking, Mono-S ion-exchange fast protein liquid chromatography (FPLC), and peptide-sequencing data confirmed the homogeneity of the extensin preparation. Evidence that the purified protein was extensin is attributed to the presence of the putative sequence motif — Ser (Hyp)4 — within the N-terminal end of the protein. Treatment of extensin with trifluoroacetic acid demonstrated that arabinose was the principal carbohydrate. The amino-acid composition of the purified extensin was similar to those reported in the literature. The cross-linking of extensin in vitro upon incubation with extensin peroxidase and exogenous H2O2 was characteristic of other reported extensins. Furthermore, Mono-S ion-exchange FPLC of native extensin precursor resolved it into two isoforms, A (90%) and B (10%). The amino-acid compositions of extensin A and extensin B were found to be similar to each other and both extensins were cross-linked in vitro by extensin peroxidase.Abbreviations CM-cellulose
carboxymethyl-cellulose
- FPLC
fast protein liquid chromatography
- HF
hydrogen fluoride
- HRGP
hydroxyproline-rich glycoprotein
- Hyp
hydroxyproline
- Vc
retention volume
- TCA
trichloroacetic acid
- TFA
tri-fluoroacetic acid
This work was supported by a A.F.R.C. postdoctoral assistantship to Michael D. Brownleader. We thank Dr. Anthony K. Allen (Department of Biochemistry, Charing Cross and Westminster Hospital, London, UK) for performing the amino-acid analysis and Mrs. Margaret Pickering (Department of Biochemistry, Royal Holloway) for performing the peptide-sequence analysis of extensin. We also express our gratitide to Dr. A. Mort (Oklahoma State University) for performing the HF-deglycosylation of extensin. 相似文献