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991.
992.
Anne‐Stéphanie Rueff Arnaud Chastanet Julia Domínguez‐Escobar Zhizhong Yao James Yates Maria‐Victoria Prejean Olivier Delumeau Philippe Noirot Roland Wedlich‐Söldner Sergio R. Filipe Rut Carballido‐López 《Molecular microbiology》2014,91(2):348-362
MreB proteins play a major role during morphogenesis of rod‐shaped bacteria by organizing biosynthesis of the peptidoglycan cell wall. However, the mechanisms underlying this process are not well understood. In Bacillus subtilis, membrane‐associated MreB polymers have been shown to be associated to elongation‐specific complexes containing transmembrane morphogenetic factors and extracellular cell wall assembly proteins. We have now found that an early intracellular step of cell wall synthesis is also associated to MreB. We show that the previously uncharacterized protein YkuR (renamed DapI) is required for synthesis of meso‐diaminopimelate (m‐DAP), an essential constituent of the peptidoglycan precursor, and that it physically interacts with MreB. Highly inclined laminated optical sheet microscopy revealed that YkuR forms uniformly distributed foci that exhibit fast motion in the cytoplasm, and are not detected in cells lacking MreB. We propose a model in which soluble MreB organizes intracellular steps of peptidoglycan synthesis in the cytoplasm to feed the membrane‐associated cell wall synthesizing machineries. 相似文献
993.
Jafar Mohseni Chia Boon Hock Che Abdul Razak Syah Nor Iman Othman Fatemeh Hayati Winnie Ong PeiTee Muzhirah Haniffa Bin Alwi Zilfalil Rowani Mohd. Rawi Lock-Hock Ngu Teguh Haryo Sasongko 《Gene》2014
Background
Hyperargininemia is a very rare progressive neurometabolic disorder caused by deficiency of hepatic cytosolic arginase I, resulting from mutations in the ARG1 gene. Until now, some mutations were reported worldwide and none of them were of Southeast Asian origins. Furthermore, most reported mutations were point mutations and a few others deletions or insertions.Objective
This study aims at identifying the disease-causing mutation in the ARG1 gene of Malaysian patients with hyperargininemia.Methodology
We employed a series of PCR amplifications and direct sequencing in order to identify the mutation. We subsequently used quantitative real-time PCR to determine the copy number of the exons flanking the mutation. We blasted our sequencing data with that of the reference sequence in the NCBI in order to obtain positional insights of the mutation.Results
We found a novel complex re-arrangement involving insertion, inversion and gross deletion of ARG1 (designated g.insIVS1 + 1899GTTTTATCAT;g.invIVS1 + 1933_ + 1953;g.delIVS1 + 1954_IVS2 + 914;c.del116_188;p.Pro20SerfsX4) commonly shared by 5 patients with hyperargininemia, each originating from different family. None of the affected families share known relationship with each other, although four of the five patients were known to have first-cousin consanguineous parents.Conclusion
This is the first report of complex re-arrangement in the ARG1. Further analyses showing that the patients have shared the same geographic origin within the northeastern part of Malaysia prompted us to suggest a simple molecular screening of hyperargininemia within related ethnicities using a long-range PCR. 相似文献994.
Shiv Poojan Anupam Dhasmana Qazi Mohammad Sajid Jamal Mohd Haneef Mohtashim Lohani 《Bioinformation》2014,10(8):474-479
Arsenic is the most toxic metalloid present in the natural environment in both organic and inorganic arsenic forms. Inorganic
arsenic is often more hazardous than the organic form. Arsenite and arsenate compounds are the major inorganic forms which are
toxic causing severe human health dysfunction including cancer. Excretion of arsenic from the system is found elusive. Therefore, it
is of interest to screen channel proteins with the arsenic complex in the different combination of arsenic, GSH (glutathione) and
arsenic, selenium using docking methods. The mode of arsenic removal. The complex structure revealed the mode of arsenic
binding efficiency with the receptor aquaporine 9 and ABCC1 channel protein. This provides insights to understand the
mechanism of arsenic efflux. These inferences find application in the design, identification and development of novel nutracetucal
or any other formulation useful in the balance of arsenic efflux. 相似文献
995.
Dinesh Chandra Sharma Mohd Sajid Khan M Salman Khan Rashmi Srivastava Ashwini Kumar Srivastava Ritu Shukla 《Bioinformation》2014,10(5):316-319
The occurrence of a large number of fossil woods having resemblance in anatomical features with the modern palm genus, Phoenix
L in Deccan Intertrappean fossil flora of Maastrichtian-Danian age (i. e. Late Cretaceous and Earliest Tertiary (65-67 my)) indicates
the most primitive record of date palm. Present discovery of biocompounds from fossil wood of Phoenix collected from Deccan
Intertrappean having affinity with the biocompounds known from modern plant further exemplify the earliest documentation of
Phoenix in Indian peninsula. 相似文献
996.
The distribution of resistance to ampicillin, chloramphenicol, sulfonamides, tetracycline, and streptomycin among coliform in the
Gomti river water samples was investigated. The coliform populations were isolated on Mac Conky and eosin methylene blue
(EMB) agar plates supplemented with antibiotics. The incidence of resistance among the coliform population varied considerably
in different drug and water sampling sites. Coliform bacteria showed lower drug resistant viable count in sampling site-III
(receiving treated wastewater) as compared to more polluted site-I and site-II. Viable count of coliform population obtained on
both medium was recorded higher against erythromycin from sampling site-III. Lower viable count of coliforms was recorded
against tetracycline in site-II and III. Similar resistance pattern was obtained in the frequency of E. coli and Enterobacter species
from all the three sampling sites. Percentage of antibiotic resistant E. coli was observed higher than Enterobacter spp among the
total coliforms against all antibiotics tested without Erythromycin and penicillin in site-I and II respectively. Isolates of E. coli and
Enterobacter spp. showed their tolerance level (MIC) in the range of 2-100 against the antibiotics tested. Maximum number of
isolates of both genus exhibited their MICs at lower concentration range 2-5µg/ml against ciprofloxacin, tetracyclin and
amoxycillin.
Abbreviations
EMB - Eosin methylene blue, IMViC tests - Indole, Methyl Red, Voges Proskauer and Citrate Utilization Tests, MIC - Minimum inhibitory concentration. 相似文献997.
Study of antibiotic resistance was done among the metal tolerant E. coli isolates from hospital wastewater at Lucknow city. Metal
tolerance was determined in terms of visible growth on metal amended plates at their varying concentrations. MICs were also
determined among all metal tolerant E. coli isolates. All the isolates showed their MIC in between 100-2000 µg/ml while maximum
isolates demonstrated their MICs at 400, 800 and 1600 µg/ml against all the metal tested. 23.07% of the isolates showed their MIC at
2000 µg/ml against Ni3+. Multiple antibiotic resistances were recorded among all the metal resistant E.coli isolates. A high level of
resistance was observed against Methicillin (86.53%) followed by penicillin (73.07%), Cephradin (57.69%), Rifampicin (34.61%),
Erythromycin (26.92%), Nalidixic acids (25%), Chloramphenicol (3.84%) and least to Gentamycine (1.92%). Streptomycin was
recorded most effective against E.coli isolates among the entire antibiotic tested. Antimicrobial resistance observed among the
bacteria from the aquatic system contaminated with hospital wastes may be threatful for the environment and public health both. 相似文献
998.
N. Navarro-Gonzalez M. Ugarte-Ruiz M. C. Porrero L. Zamora G. Mentaberre E. Serrano A. Mateos S. Lavín L. Domínguez 《EcoHealth》2014,11(3):333-342
Campylobacter infections are a public health concern and an increasingly common cause of food-borne zoonoses in the European Union. However, little is known about their spill-over from free-ranging livestock to sympatric wild ungulates, especially in regards to uncommon Campylobacter species. In this study, we aim to determine the prevalence of C. coli, C. jejuni and other C. spp. in game ungulates (wild boar Sus scrofa and Iberian ibex Capra pyrenaica) and free-ranging sympatric cattle in a National Game Reserve in NE Spain. Furthermore, we explore the extent to which Campylobacter species are shared among these co-habiting hosts. Faecal samples from Iberian ibex (n = 181) were negative for C. spp. By direct plating, two wild boars out of 150 were positive for C. coli (1.3%, 95% CI 0.16–4.73), and one was positive for C. jejuni (0.67%, 95% CI 0.02–3.66). The latter was predominant in cattle: 5.45% (n = 55, 95% CI 1.14–5.12), while C. coli was not isolated from this host. C. lanienae was the most frequent species in wild boar at 10% (95% CI 5.7–15.96), and one cow cohabiting with positive wild boars in the same canyon also carried C. lanienae. Four enrichment protocols (using Bolton or Preston broth combined with either mCCDA or CFA) were added for 172 samples (57 from wild boars, 55 cattle and 60 Iberian ibexes) to increase the number of isolates obtained allowing the detection of statistically significant differences. The prevalence of C. lanienae was statistically significantly higher in wild boar than in cattle (P < 0.01), but the prevalence of C. jejuni was higher in the latter (P = 0.045). These results suggest that wild boar and cattle carry their own predominant Campylobacter species, while Iberian ibex do not seem to play an important role in the epidemiology of Campylobacter. However, there is a potential spill-over of C. spp., and thus, further research is needed to elucidate the factors determining inter-species transmission. 相似文献
999.
High‐Performance Semitransparent Tandem Solar Cell of 8.02% Conversion Efficiency with Solution‐Processed Graphene Mesh and Laminated Ag Nanowire Top Electrodes
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Abd. Rashid bin Mohd Yusoff Seung Joo Lee Fabio Kurt Shneider Wilson Jose da Silva Jin Jang 《Liver Transplantation》2014,4(12)
A high‐performance semitransparent tandem solar cell that uses solution‐processed graphene mesh and laminated Ag NW as a transparent anode and cathode, respectively, is demonstrated. The laminated top electrode can be deposited without causing any damage to the underneath organic solar cells. Power conversion efficiencies of 8.02% and 6.47% are obtained when the light is projected from the solution‐processed graphene mesh and laminated AgNW, respectively. The performance of the tandem cell is found to be comparable to a tandem solar cell fabricated using commercially available indium tin oxide. These findings offer a high‐performance device and open a new pathway in searching for a potential replacement to the frequently used transparent conducting electrodes. 相似文献
1000.
Ponnarasy Ganasen Maksudur Rahman Khan M. Abul Kalam Mohd Sabri Mahmud 《Bioprocess and biosystems engineering》2014,37(11):2353-2359
This paper demonstrates Pseudomonas cepacia lipase catalyzed hydrolysis of p-nitrophenyl palmitate under irradiation of light with wavelengths of 250–750 nm. The reaction follows Michaelis–Menten Kinetics and the light irradiation increases the overall rate of hydrolysis. Using Lineweaver–Burk plot K M and V max values for the reaction in presence of light are found to be 39.07 and 66.67 mM/min/g, respectively; while for the same reaction under dark condition, the values are 7.08 and 10.21 mM/min/g. The linear form of enzyme dependent rate of reaction confirms that no mass-transfer limitations are present and the reaction is a kinetically controlled enzymatic reaction. 相似文献