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In this study fecal microflora of human infants born through vaginal delivery (VB) and through cesarean section (CB) were investigated using culture-independent 16S rDNA cloning and sequencing approach. The results obtained clearly revealed that fecal microbiota of VB infants distinctly differ from those in their counterpart CB infants. The intestinal microbiota of infants delivered by cesarean section appears to be more diverse, in terms of bacteria species, than the microbiota of vaginally delivered infants. The most abundant bacterial species present in VB infants were Acinetobacter sp., Bifidobacterium sp. and Staphylococcus sp. However, CB infant’s fecal microbiota was dominated with Citrobacter sp., Escherichia coli and Clostridium difficile. The intestinal microbiota of cesarean section delivered infants in this study was also characterized by an absence of Bifidobacteria species. An interesting finding of our study was recovery of large number of Acinetobacter sp. consisting of Acinetobacter pittii (former Acinetobacter genomic species 3), Acinetobacter junii and Acinetobacter baumannii in the VB infants clone library. Among these, Acinetobacter baumannii is a known nosocomial pathogen and Acinetobacter pittii (genomic species 3) is recently recognized as clinically important taxa within the Acinetobacter calcoaceticusAcinetobacter baumannii (ACB) complex. Although none of the infants had shown any sign of clinical symptoms of disease, this observation warrants a closer look.  相似文献   
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Obesity is a consequence of a complex interplay between the host genome and the prevalent obesogenic factors among the modern communities. The role of gut microbiota in the pathogenesis of the disorder was recently discovered; however, 16S-rRNA-based surveys revealed compelling but community-specific data. Considering this, despite unique diets, dietary habits and an uprising trend in obesity, the Indian counterparts are poorly studied. Here, we report a comparative analysis and quantification of dominant gut microbiota of lean, normal, obese and surgically treated obese individuals of Indian origin. Representative gut microbial diversity was assessed by sequencing fecal 16S rRNA libraries for each group (n=5) with a total of over 3000 sequences. We detected no evident trend in the distribution of the predominant bacterial phyla, Bacteroidetes and Firmicutes. At the genus level, the bacteria of genus Bacteroides were prominent among the obese individuals, which was further confirmed by qPCR (P less than 0.05). In addition, a remarkably high archaeal density with elevated fecal SCFA levels was also noted in the obese group. On the contrary, the treated-obese individuals exhibited comparatively reduced Bacteroides and archaeal counts along with reduced fecal SCFAs. In conclusion, the study successfully identified a representative microbial diversity in the Indian subjects and demonstrated the prominence of certain bacterial groups in obese individuals; nevertheless, further studies are essential to understand their role in obesity.  相似文献   
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House flies (Musca domestica L.) are cosmopolitan, ubiquitous, synanthropic insects that serve as mechanical or biological vectors for various microorganisms. To fully assess the role of house flies in the epidemiology of human diseases, it is essential to understand the diversity of microbiota harbored by natural fly populations. This study aimed to identify the diversity of house fly gut bacteria by both culture-dependent and culture-independent approaches. A total of 102 bacterial strains were isolated from the gut of 65 house flies collected from various public places including a garden, public park, garbage/dump area, public toilet, hospital, restaurant/canteen, mutton shop/market, and house/human habitation. Molecular phylogenetic analyses placed these isolates into 22 different genera. The majority of bacteria identified were known potential pathogens of the genera Klebsiella, Aeromonas, Shigella, Morganella, Providencia, and Staphylococcus. Culture-independent methods involved the construction of a 16S rRNA gene clone library, and sequence analyses supported culture recovery results. However, additional bacterial taxa not determined via culture recovery were revealed using this methodology and included members of the classes Alphaproteobacteria, Deltaproteobacteria, and the phylum Bacteroidetes. Here, we show that the house fly gut is an environmental reservoir for a vast number of bacterial species, which may have impacts on vector potential and pathogen transmission.  相似文献   
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Summary An agar-degrading bacterium capable of utilizing agar as sole source of carbon and energy was isolated from sea water by enrichment culture technique. The bacterium was identified as Pseudomonas aeruginosa and the culture conditions were standardized for the maximal production of extracellular agarases. The bacterium grew in the pH range 5.0–11.0, optimal between pH 7.0 and 8.0; temperature between 25 °C and 37 °C, optimal at 30 °C and sodium chloride concentration 0–8% and optimal at 2% respectively. The agarases secreted by Pseudomonas aeruginosa AG LSL-11 were inducible by agar and not by any other simple sugars tested. Maximal agarase production was observed at pH 8.0, and temperature 30 °C. The bacterium had no requirement for NaCl for both growth and production of agarases. The bacterium did not utilize other polysaccharides like ĸ-carrageenan, alginate, cellulose and CMC. The activity staining of partially purified agarase preparation after native-PAGE revealed the presence of three different agarases, agarase LSL-11a, LSL-11b and LSL-11c, whose molecular weights were estimated to be 76, 64 and 46 kDa respectively.  相似文献   
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A new cell line from the embryonic tissue of Helicoverpa armigera was established and designated as NIV-HA-197. It was maintained in TNM-FH medium supplemented with 10% fetal bovine serum. The cell line at passage 20 had a heterogeneous population of cells consisting of mainly epithelial-like cells (70%), followed by fibroblast-like (27%), and multinucleated giant (3%) cells. The chromosome number ranged from 45 to 185. The growth curve at passage 40 showed a fivefold increase in cell number with a population-doubling time of approximately 60 h. The cell line was found infected with the microsporidium Nosema heliothids at passage 9. Using the antiprotozoan drug Metrogyl 400 and simultaneous heat treatment, the parasite was removed from the culture. The cell line can be cryopreserved for 30 mo. The species specificity of the new cell line was determined by studying the isoenzyme profile of four enzymes, viz., lactate dehydrogenase, malate dehydrogenase, isocitrate dehydrogenase, and glucose 6-phosphate dehydrogenase, and by heteroduplex analysis. Heteroduplex analysis was used to analyze the mitochondrial 16S ribosomal ribonucleic acid gene sequences along with the host insect gene sequences, and 100% homology was obtained, confirming the conspecificity of the cell line. The cell line was found to be susceptible to the baculoviruses Autographa californica multiple nucleopolyhedrovirus, Spodoptera litura multiple nucleopolyhedrovirus, and H. armigera single nucleopolyhedrovirus (HaSNPV). More than 90% of the cells were infected by HaSNPV on the seventh post infection day (PID), and 28.8 x 10(6) NPV/ml was yielded on the 10th PID. The in vitro-grown HaSNPV caused 100% mortality, when fed to the second instar H. armigera larvae, in 6 d. Cessation of feeding was observed on the second PID.  相似文献   
27.
Feasibility of using chocolate industry wastewater as a substrate for electricity generation using activated sludge as a source of microorganisms was investigated in two-chambered microbial fuel cell. The maximum current generated with membrane and salt bridge MFCs was 3.02 and 2.3 A/m2, respectively, at 100 Ω external resistance, whereas the maximum current generated in glucose powered MFC was 3.1 A/m2. The use of chocolate industry wastewater in cathode chamber was promising with 4.1 mA current output. Significant reduction in COD, BOD, total solids and total dissolved solids of wastewater by 75%, 65%, 68%, 50%, respectively, indicated effective wastewater treatment in batch experiments. The 16S rDNA analysis of anode biofilm and suspended cells revealed predominance of β-Proteobacteria clones with 50.6% followed by unclassified bacteria (9.9%), α-Proteobacteria (9.1%), other Proteobacteria (9%), Planctomycetes (5.8%), Firmicutes (4.9%), Nitrospora (3.3%), Spirochaetes (3.3%), Bacteroides (2.4%) and γ-Proteobacteria (0.8%). Diverse bacterial groups represented as members of the anode chamber community.  相似文献   
28.
Heavy metals, being phytotoxic, cause growth inhibition and even plant death. Siderophore-producing bacterial strain KNP9 is growth promoting and has been isolated from Panki Power Plant, Kanpur, India. It simulated significant (p > 5%) root and shoot growth of mung bean to the extent of 16.48% and 28.80%, respectively in the presence of CdCl2 (110 M). However, the increase in root and shoot growth was 20% and 19.5%, respectively, in the presence of (CH3COO)2Pb (660 M). Moreover, concentration of accumulated lead and cadmium in root and shoot was also reduced in the presence of this isolate ranging from 37.5 to 93.19%. A moderate reduction in chlorophyll content (39.14%) in the presence of 110 M CdCl2 was rescued by bioinoculant KNP9. However, the 19.58% decrease in chlorophyll content in the case of lead acetate remained unchanged even in the presence of KNP9. Nevertheless, 16S ribosomal DNA (rDNA) sequencing identified KNP9 as a strain of Pseudomonas putida.  相似文献   
29.
The polymorphism of the 18S rRNA gene in Wuchereria bancrofti microfilariae (mf) collected from three different zones in India was analyzed by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). The RFLPs of the amplified products obtained after digestion with restriction enzymes Ssp I, Msp I and Hha I showed no difference in the banding patterns among the mf isolates from different endemic zones. Further the sequencing of PCR products did not show any difference in the nucleotide sequence either. The phylogenetic analysis of the sequences of W. bancrofti mf isolates from different endemic zones has shown branching with the earlier reported sequences of W. bancrofti and its close relative Brugia malayi.  相似文献   
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