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1.
S. Wehmeier A. S. Varghese S. S. Gurcha B. Tissot M. Panico P. Hitchen H. R. Morris G. S. Besra A. Dell M. C. M. Smith 《Molecular microbiology》2009,71(2):421-433
Previously mutations in a putative protein O -mannosyltransferase (SCO3154, Pmt) and a polyprenol phosphate mannose synthase (SCO1423, Ppm1) were found to cause resistance to phage, φC31, in the antibiotic producing bacteria Streptomyces coelicolor A3(2). It was proposed that these two enzymes were part of a protein O-glycosylation pathway that was necessary for synthesis of the phage receptor. Here we provide the evidence that Pmt and Ppm1 are indeed both required for protein O-glycosylation. The phosphate binding protein PstS was found to be glycosylated with a trihexose in the S. coelicolor parent strain, J1929, but not in the pmt − derivative, DT1025. Ppm1 was necessary for the transfer of mannose to endogenous polyprenol phosphate in membrane preparations of S. coelicolor . A mutation in ppm1 that conferred an E218V substitution in Ppm1 abolished mannose transfer and glycosylation of PstS. Mass spectrometry analysis of extracted lipids showed the presence of a glycosylated polyprenol phosphate (PP) containing nine repeated isoprenyl units (C45 -PP). S. coelicolor membranes were also able to catalyse the transfer of mannose to peptides derived from PstS, indicating that these could be targets for Pmt in vivo . 相似文献
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The anthers of three genotypes ofLycopersicon esculentum, viz. cv. HS-101, cv. HS-102 and an F1 hybrid (Montfavet 63-4xHS-101) in different stages of development were cultured in various defined nutritive media. Only
anthers containing microspores in the early uninucleate stage were found to respond with the culture medium in the formation
of androgenic callus. The DGII medium with 2 mg l−1 NAA and 1 mg 1−1 kinetin was found to be best for callus induction but MS medium supplemented with 2 mg l−1 2,4-D and 0.1 mg 1−1 BAP favoured proliferation and growth of the callus. The androgenic microspores followed the ‘B’ type pathway of androgenesis
in the formation of callus.
Induction of tracheids in the callus could be achieved by supplementing the basal medium with NAA and kinetin or 2,4-D and
BAP. Initiation of vessel elements and cambium were favoured by addition of NAA and kinetin and that of the phloem in the
presence of 2,4-D and BAP in the basal medium, suggesting that the hormonal requirements for production of different elements
of the vascular system in androgenic callus are different. Although roots could be induced from the callus, shoot differentiation
could not be achieved under cultural conditions. 相似文献
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Bacterial spot of tomato and pepper: diverse Xanthomonas species with a wide variety of virulence factors posing a worldwide challenge 下载免费PDF全文
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Ana Gorostidi Alberto Bergareche Javier Ruiz-Martínez José F. Martí-Massó María Cruz Shiji Varghese Mohamed M. Qureshi Fatimah Alzahmi Abdulmonem Al-Hayani Adolfo López de Munáin Omar M.A. El-Agnaf 《PloS one》2012,7(12)
The diagnosis of Parkinson’s disease (PD) remains primarily a clinical issue, based mainly on phenotypic patterns. The identification of biomarkers capable of permitting the preclinical detection of PD is critically needed. α-Synuclein is a key protein in PD, with missense and multiplication mutations in the gene encoding α-synuclein (SNCA) having been reported in familial cases of PD, and accumulation of the protein identified in Lewy bodies (LBs) and Lewy neurites (LNs) in affected brain regions. With the objective of validating the use of α-synuclein as a clinical or progressive biomarker in an accessible tissue, we used an enzyme-linked immunosorbent assay (ELISA) to measure α-synuclein levels in the peripheral blood plasma of idiopathic PD and LRRK2 mutation carrier patients and compared our findings with healthy control subjects. Compared to healthy controls, we found a significant decrease in plasma total α-synuclein levels in idiopathic PD (iPD) patients (n = 134, p = 0.010). However, the reduction was less significant in patients who were LRRK2 mutation carriers (n = 32, p = 0.133). This lack of significance could be due to the small number of individuals employed in this group. No predictive value of total α-synuclein in the diagnosis of PD was found in a receiver operating characteristic (ROC) curve analysis. Although this is a pilot study requiring corroboration on a larger cohort of patients, our results highlight the possible use of plasma α-synuclein as a biomarker for PD. 相似文献
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Clinical decision is often difficult with chlorhexidine mouthwash. The use of antioxidant mouthwashes for the treatment of periodontal disease is in practise. Therefore, it is of interest to collect gleaned information on Antioxidant mouthwashes as periodontal therapy from known literature. Improvement in treatment using antioxidant mouthwashes is reported in several studies. The mouthwash with antioxidants has similar anti-gingivitis, antiplaque and antimicrobial effects as that of chlorhexidine mouthwash. 相似文献
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Neha J. Pagidipati Mark D. Huffman Panniyammakal Jeemon Rajeev Gupta Prakash Negi Thannikot M. Jaison Satyavan Sharma Nakul Sinha Padinhare Mohanan B. G. Muralidhara Sasidharan Bijulal Sivasubramonian Sivasankaran Vijay K. Puri Jacob Jose K. Srinath Reddy Dorairaj Prabhakaran 《PloS one》2013,8(4)