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1.
Sellappan Saravanan Venketaraman Purushothaman Thippichettypalayam Ramasamy Gopala Krishna Murthy Kuppannan Sukumar Palani Srinivasan Vasudevan Gowthaman Mohan Balusamy Robert Atterbury Suresh V. Kuchipudi 《Indian journal of microbiology》2015,55(3):319-326
Human infections with non-typhoidal Salmonella (NTS) serovars are increasingly becoming a threat to human health globally. While all motile Salmonellae have zoonotic potential, Salmonella Enteritidis and Salmonella Typhimurium are most commonly associated with human disease, for which poultry are a major source. Despite the increasing number of human NTS infections, the epidemiology of NTS in poultry in India has not been fully understood. Hence, as a first step, we carried out epidemiological analysis to establish the incidence of NTS in poultry to evaluate the risk to human health. A total of 1215 samples (including poultry meat, tissues, egg and environmental samples) were collected from 154 commercial layer farms from southern India and screened for NTS. Following identification by cultural and biochemical methods, Salmonella isolates were further characterized by multiplex PCR, allele-specific PCR, enterobacterial repetitive intergenic consensus (ERIC) PCR and pulse field gel electrophoresis (PFGE). In the present study, 21/1215 (1.73 %) samples tested positive for NTS. We found 12/392 (3.06 %) of tissue samples, 7/460 (1.52 %) of poultry products, and 2/363 (0.55 %) of environmental samples tested positive for NTS. All the Salmonella isolates were resistant to oxytetracycline, which is routinely used as poultry feed additive. The multiplex PCR results allowed 16/21 isolates to be classified as S. Typhimurium, and five isolates as S. Enteritidis. Of the five S. Enteritidis isolates, four were identified as group D Salmonella by allele-specific PCR. All of the isolates produced different banding patterns in ERIC PCR. Of the thirteen macro restriction profiles (MRPs) obtained by PFGE, MRP 6 was predominant which included 6 (21 %) isolates. In conclusion, the findings of the study revealed higher incidence of contamination of NTS Salmonella in poultry tissue and animal protein sources used for poultry. The results of the study warrants further investigation on different type of animal feed sources, food market chains, processing plants, live bird markets etc., to evaluate the risk factors, transmission and effective control measures of human Salmonella infection from poultry products. 相似文献
2.
《Molecular & cellular proteomics : MCP》2020,19(2):233-244
Highlights
- •Mapping kinase-substrate relationships is vital in discovering new tuberculosis drug targets.
- •LC-MS/MS-based phosphoproteomics expand mycobacterial STPK substrate catalogues.
- •We review and integrate MS-generated datasets on novel candidate substrates.
- •Validation studies are necessary to confirm true physiological substrates of STPKs.
3.
《Saudi Journal of Biological Sciences》2017,24(8):1842-1848
Due to the feature of high hydrolysis, tannase is widely used in food, beverage, brewing and other fields. However, high cost in producing natural tannase makes it difficult to apply tannase to industry in a large-scale. Microbial expression systems can be used for preparing numerous amount of enzyme at low cost, so in this paper Aspergillus niger N5-5 was expressed using E. coli system. Specific primers were designed based on the Aspergillus niger N5-5 sequence N3 (GenBank, No.: KP677552), and tannase gene tan was promoted to carry 6 His tag and enzyme cutting site which contains NdeI/HindIII using PCR amplification. Then, tannase gene tan was connected to expression vector by NdeI/HindIII enzyme cutting. In this way, recombinant expression vector tan-pET43.1a was formed. Then, the expression vector pET43.1a by NdeI/HindIII enzyme cutting was transformed into E. coli BL21 (DE3) to induce expression of Aspergillus niger N5-5. When the induced fungi were disrupted by the ultrasonic wave, the crude enzyme was extracted and purified by using the IMAC, and then the activity of the crude enzyme and pure enzyme was determined. According to the results of determination of the tannase activity, the tannase activity of the crude enzyme was greatly improved after the crude enzyme was purified, and the specific activity of the pure enzyme was about 8 times of that of the crude enzyme. The results of SDS-PAGE of the pure enzyme showed that the molecular mass of the pure enzyme was about 65 kDa/64–65 kDa, which was consistent with the expected result (64.2 kDa), It can be concluded that the crude enzyme solution was purified successfully. The results of pure enzyme’s protein identification by Western Blotting showed that clear protein bands pro-3 were observed. Molecular mass of clear protein bands pro-3 was about 65 kDa, which was in line with the expected results (64.2 kDa). It can be seen that the aforementioned expression protein could be specifically combined with His tag. It proved expression protein to be a recombinant fusion protein with 6 His tag. 相似文献
4.
Brachypalpus (Brachypalpus) longifacies sp. nov. is described and illustrated from Eastern Asia (Russian Far East and Japan). It differs from other species of the nominative subgenus by several unusual characters, i.e. face in profile weakly convex dorsally and concave ventrally, antennae very elongated, and abdomen with reddish transversal maculae on 2nd tergum (male) or 2nd and 3rd terga (female). A key is given for known species of the subgenus Brachypalpus.LSID: urn:lsid:zoobank.org:pub:634CB6E2-B2C1-40EC-8811-BF3DD4BDE69A 相似文献
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《Molecular & cellular proteomics : MCP》2019,18(1):65-85
Highlights
- •Natural substrates of FAP were identified using degradomic and proteomic techniques and FAP gene knockout mouse derived embryonic fibroblasts stably transduced with enzymatically active or inactive FAP.
- •Terminal amine isotopic labelling of substrates (TAILS) based degradomics identified cleavage sites in collagens, and many other extracellular matrix (ECM) and associated proteins.
- •Cleavages of lysyl oxidase-like-1, CXCL-5, CSF-1 and C1qT6 by FAP were confirmed in vitro.
- •Differential metabolic labelling coupled with quantitative proteomic analysis implicated FAP in regulating proteins that are associated with ECM, ECM-cell interactions, coagulation, metabolism and wound healing.
10.
《Molecular & cellular proteomics : MCP》2019,18(6):1227-1241
Highlights
- •Quantitative microproteomics to study the CNS and PNS of the Twitcher mouse.
- •10plex TMT experiments on corpus callosum, motor cortex and sciatic nerves extracts.
- •More than 400 proteins groups deregulated between Twitcher and wildtype mice.
- •New insights into the molecular mechanisms of Krabbe disease.