Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 41
Filtrar
1.
Persoonia ; 42: 291-473, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31551622

RESUMO

Novel species of fungi described in this study include those from various countries as follows: Australia, Chaetomella pseudocircinoseta and Coniella pseudodiospyri on Eucalyptus microcorys leaves, Cladophialophora eucalypti, Teratosphaeria dunnii and Vermiculariopsiella dunnii on Eucalyptus dunnii leaves, Cylindrium grande and Hypsotheca eucalyptorum on Eucalyptus grandis leaves, Elsinoe salignae on Eucalyptus saligna leaves, Marasmius lebeliae on litter of regenerating subtropical rainforest, Phialoseptomonium eucalypti (incl. Phialoseptomonium gen. nov.) on Eucalyptus grandis × camaldulensis leaves, Phlogicylindrium pawpawense on Eucalyptus tereticornis leaves, Phyllosticta longicauda as an endophyte from healthy Eustrephus latifolius leaves, Pseudosydowia eucalyptorum on Eucalyptus sp. leaves, Saitozyma wallum on Banksia aemula leaves, Teratosphaeria henryi on Corymbia henryi leaves. Brazil, Aspergillus bezerrae, Backusella azygospora, Mariannaea terricola and Talaromyces pernambucoensis from soil, Calonectria matogrossensis on Eucalyptus urophylla leaves, Calvatia brasiliensis on soil, Carcinomyces nordestinensis on Bromelia antiacantha leaves, Dendryphiella stromaticola on small branches of an unidentified plant, Nigrospora brasiliensis on Nopalea cochenillifera leaves, Penicillium alagoense as a leaf endophyte on a Miconia sp., Podosordaria nigrobrunnea on dung, Spegazzinia bromeliacearum as a leaf endophyte on Tilandsia catimbauensis, Xylobolus brasiliensis on decaying wood. Bulgaria, Kazachstania molopis from the gut of the beetle Molops piceus. Croatia, Mollisia endocrystallina from a fallen decorticated Picea abies tree trunk. Ecuador, Hygrocybe rodomaculata on soil. Hungary, Alfoldia vorosii (incl. Alfoldia gen. nov.) from Juniperus communis roots, Kiskunsagia ubrizsyi (incl. Kiskunsagia gen. nov.) from Fumana procumbens roots. India, Aureobasidium tremulum as laboratory contaminant, Leucosporidium himalayensis and Naganishia indica from windblown dust on glaciers. Italy, Neodevriesia cycadicola on Cycas sp. leaves, Pseudocercospora pseudomyrticola on Myrtus communis leaves, Ramularia pistaciae on Pistacia lentiscus leaves, Neognomoniopsis quercina (incl. Neognomoniopsis gen. nov.) on Quercus ilex leaves. Japan, Diaporthe fructicola on Passiflora edulis × P. edulis f. flavicarpa fruit, Entoloma nipponicum on leaf litter in a mixed Cryptomeria japonica and Acer spp. forest. Macedonia, Astraeus macedonicus on soil. Malaysia, Fusicladium eucalyptigenum on Eucalyptus sp. twigs, Neoacrodontiella eucalypti (incl. Neoacrodontiella gen. nov.) on Eucalyptus urophylla leaves. Mozambique, Meliola gorongosensis on dead Philenoptera violacea leaflets. Nepal, Coniochaeta dendrobiicola from Dendriobium lognicornu roots. New Zealand, Neodevriesia sexualis and Thozetella neonivea on Archontophoenix cunninghamiana leaves. Norway, Calophoma sandfjordenica from a piece of board on a rocky shoreline, Clavaria parvispora on soil, Didymella finnmarkica from a piece of Pinus sylvestris driftwood. Poland, Sugiyamaella trypani from soil. Portugal, Colletotrichum feijoicola from Acca sellowiana. Russia, Crepidotus tobolensis on Populus tremula debris, Entoloma ekaterinae, Entoloma erhardii and Suillus gastroflavus on soil, Nakazawaea ambrosiae from the galleries of Ips typographus under the bark of Picea abies. Slovenia, Pluteus ludwigii on twigs of broadleaved trees. South Africa, Anungitiomyces stellenboschiensis (incl. Anungitiomyces gen. nov.) and Niesslia stellenboschiana on Eucalyptus sp. leaves, Beltraniella pseudoportoricensis on Podocarpus falcatus leaf litter, Corynespora encephalarti on Encephalartos sp. leaves, Cytospora pavettae on Pavetta revoluta leaves, Helminthosporium erythrinicola on Erythrina humeana leaves, Helminthosporium syzygii on a Syzygium sp. bark canker, Libertasomyces aloeticus on Aloe sp. leaves, Penicillium lunae from Musa sp. fruit, Phyllosticta lauridiae on Lauridia tetragona leaves, Pseudotruncatella bolusanthi (incl. Pseudotruncatellaceae fam. nov.) and Dactylella bolusanthi on Bolusanthus speciosus leaves. Spain, Apenidiella foetida on submerged plant debris, Inocybe grammatoides on Quercus ilex subsp. ilex forest humus, Ossicaulis salomii on soil, Phialemonium guarroi from soil. Thailand, Pantospora chromolaenae on Chromolaena odorata leaves. Ukraine, Cadophora helianthi from Helianthus annuus stems. USA, Boletus pseudopinophilus on soil under slash pine, Botryotrichum foricae, Penicillium americanum and Penicillium minnesotense from air. Vietnam, Lycoperdon vietnamense on soil. Morphological and culture characteristics are supported by DNA barcodes.

2.
Med Vet Entomol ; 30(3): 264-77, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27094337

RESUMO

Dengue viruses are transmitted to humans through the bites of infected female aedine mosquitoes. Differences in the composition and structure of bacterial communities in the midguts of mosquitoes may affect the vector's ability to transmit the disease. To investigate and analyse the role of midgut bacterial communities in viral transmission, midgut bacteria from three species, namely Stegomyia aegypti (= Aedes aegypti), Fredwardsius vittatus (= Aedes vittatus) and Stegomyia albopicta (= Aedes albopictus) (all: Diptera: Culicidae), from dengue-endemic and non-endemic areas of Rajasthan, India were compared. Construction and analyses of six 16S rRNA gene libraries indicated that Serratia spp.-related phylotypes dominated all clone libraries of the three mosquito species from areas in which dengue is not endemic. In dengue-endemic areas, phylotypes related to Aeromonas, Enhydrobacter spp. and uncultivated bacterium dominated the clone libraries of S. aegypti, F. vittatus and S. albopicta, respectively. Diversity indices analysis and real-time TaqMan polymerase chain reaction assays showed bacterial diversity and abundance in the midguts of S. aegypti to be higher than in the other two species. Significant differences observed among midgut bacterial communities of the three mosquito species from areas in which dengue is and is not endemic, respectively, may be related to the vectorial capacity of mosquitoes to carry dengue viruses and, hence, to the prevalence of disease in some areas.


Assuntos
Aedes/microbiologia , Bactérias/isolamento & purificação , Dengue/epidemiologia , Doenças Endêmicas , Microbioma Gastrointestinal , Animais , Dengue/virologia , Feminino , Índia/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real
3.
Int J Syst Evol Microbiol ; 64(Pt 7): 2250-2256, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24711592

RESUMO

Two coccoid, non-motile, obligately anaerobic, Gram-stain-negative bacteria, occurring singly or in pairs, or as short chains, with a mean size of 1.4-2.5 µm were isolated from the faeces of two healthy human volunteers, aged 26 and 56 years, and were designated NMBHI-10(T) and BLPYG-7, respectively. Both the strains were affiliated to the sub-branch Sporomusa of the class Clostridia as revealed by 16S rRNA gene sequence analysis. The isolates NMBHI-10(T) and BLPYG-7 showed 99.1 and 99.2% 16S rRNA gene sequence similarity, respectively, with Megasphaera elsdenii JCM 1772(T). DNA-DNA hybridization and phenotypic analysis showed that both the strains were distinct from their closest relative, M. elsdenii JCM 1772(T) (42 and 53% DNA-DNA relatedness with NMBHI-10(T) and BLPYG-7, respectively), but belong to the same species (DNA-DNA relatedness of 80.9 % between the isolates). According to DNA-DNA hybridization results, the coccoid strains belong to the same genospecies, and neither is related to any of the recognized species of the genus Megasphaera. Strains NMBHI-10(T) and BLPYG-7 grew in PYG broth at temperatures of between 15 and 40 °C (optimum 37 °C), but not at 45 °C. The strains utilized a range of carbohydrates as sources of carbon and energy including glucose, lactose, cellobiose, rhamnose, galactose and sucrose. Glucose fermentation resulted in the formation of volatile fatty acids, mainly caproic acid and organic acids such as succinic acid. Phylogenetic analysis, specific phenotypic characteristics and/or DNA G+C content also differentiated the strains from each other and from their closest relatives. The DNA G+C contents of strains NMBHI-10(T) and BLPYG-7 are 57.7 and 54.9 mol%, respectively. The major fatty acids were 12 : 0 FAME and 17 : 0 CYC FAME. On the basis of these data, we conclude that strains NMBHI-10(T) and BLPYG-7 should be classified as representing a novel species of the genus Megasphaera, for which the name Megsphaera indica sp. nov. is proposed. The type strain is NMBHI-10(T) ( = DSM 25563(T) = MCC 2481(T)).


Assuntos
Fezes/microbiologia , Megasphaera/classificação , Filogenia , Adulto , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fermentação , Humanos , Índia , Masculino , Megasphaera/genética , Megasphaera/isolamento & purificação , Pessoa de Meia-Idade , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
4.
Med Vet Entomol ; 28(4): 345-54, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24805263

RESUMO

Flesh flies of the genus Sarcophaga (Diptera: Sarcophagidae) are carrion-breeding, necrophagous insects important in medical and veterinary entomology as potential transmitters of pathogens to humans and animals. Our aim was to analyse the diversity of gut-associated bacteria in wild-caught larvae and adult flesh flies using culture-dependent and culture-independent methods. Analysis of 16S rRNA gene sequences from cultured isolates and clone libraries revealed bacteria affiliated to Proteobacteria, Actinobacteria, Firmicutes and Bacteroidetes in the guts of larval and adult flesh flies. Bacteria cultured from larval and adult flesh fly guts belonged to the genera Acinetobacter, Bacillus, Budvicia, Citrobacter, Dermacoccus, Enterococcus, Ignatzschineria, Lysinibacillus, Myroides, Pasteurella, Proteus, Providencia and Staphylococcus. Phylogenetic analysis showed clone sequences of the genera Aeromonas, Bacillus, Bradyrhizobium, Citrobacter, Clostridium, Corynebacterium, Ignatzschineria, Klebsiella, Pantoea, Propionibacterium, Proteus, Providencia, Serratia, Sporosarcina, Weissella and Wohlfahrtiimonas. Species of clinically significant genera such as Ignatzschineria and Wohlfahrtiimonas spp. were detected in both larvae and adult flesh flies. Sequence analysis of 16S rRNA gene libraries supported culture-based results and revealed the presence of additional bacterial taxa. This study determined the diversity of gut microbiota in flesh flies, which will bolster the ability to assess microbiological risk associated with the presence of these flies. The present data thereby establish a platform for a much larger study.


Assuntos
Bactérias/genética , Bactérias/isolamento & purificação , Dípteros/microbiologia , Trato Gastrointestinal/microbiologia , Animais , Larva/microbiologia , Filogenia
5.
Indian J Microbiol ; 53(1): 11-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24426073

RESUMO

Kutajarista is an Ayurvedic fermented herbal formulation prescribed for gastrointestinal disorders. This herbal formulation undergoes a gradual fermentative process and takes around 2 months for production. In this study, microbial composition at initial stages of fermentation of Kutajarista was assessed by culture independent 16S rRNA gene clone library approach. Physicochemical changes were also compared at these stages of fermentation. High performance liquid chromatography-mass spectrometry analysis showed that Gallic acid, Ellagic acid, and its derivatives were the major chemical constituents recovered in this process. At 0 day of fermentation, Lactobacillus sp., Acinetobacter sp., Alcaligenes sp., and Methylobacterium sp. were recovered, but were not detected at 8 day of fermentation. Initially, microbial diversity increased after 8 days of fermentation with 11 operational taxonomic units (OTUs), which further decreased to 3 OTUs at 30 day of fermentation. Aeromonas sp., Pseudomonas sp., and Klebsiella sp. dominated till 30 day of fermentation. Predominance of γ- Proteobacteria and presence of gallolyl derivatives at the saturation stage of fermentation implies tannin degrading potential of these microbes. This is the first study to highlight the microbial role in an Ayurvedic herbal product fermentation.

6.
J Bacteriol ; 194(23): 6629-30, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23144385

RESUMO

Janibacter hoylei MTCC8307 was isolated from stratospheric air at an altitude of 41.4 km over Hyderabad, India. Here, we present the draft genome of Janibacter hoylei MTCC8307, which contains 3,139,099 bp with a G+C content of 72.8 mol%, 2,972 protein-coding genes, and 57 structural RNAs.


Assuntos
Actinomycetales/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Genoma Bacteriano , Análise de Sequência de DNA , Actinomycetales/isolamento & purificação , Microbiologia do Ar , Proteínas de Bactérias/genética , Composição de Bases , Índia , Dados de Sequência Molecular , Fases de Leitura Aberta , RNA não Traduzido/genética
7.
Mol Biol Rep ; 39(3): 2375-83, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21670958

RESUMO

We have checked the utility of DNA barcoding for species identification of nymphalid butterflies from Western Ghats of India by using 650 bp sequence of mitochondrial gene cytochrome c oxidase subunit I. Distinct DNA barcoding gap (i.e. difference between intraspecies and interspecies nucleotide divergence), exists between species studied here. When our sequences were compared with the sequences of the conspecifics submitted from different geographic regions, nine cases of deep intraspecies nucleotide divergences were observed. In spite of this, NJ (Neighbour Joining) clustering analysis successfully discriminated all species. Observed cases of deep intraspecies nucleotide divergences certainly warrant further study.


Assuntos
Borboletas/genética , Código de Barras de DNA Taxonômico/métodos , Variação Genética , Animais , Análise por Conglomerados , Biologia Computacional/métodos , Complexo IV da Cadeia de Transporte de Elétrons/genética , Índia , Especificidade da Espécie
8.
Int J Syst Evol Microbiol ; 60(Pt 10): 2387-2391, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19933582

RESUMO

A yellow-pigmented bacterial strain, R4-1A(T), isolated from the midgut of the mosquito Culex quinquefasciatus (a vector of lymphatic filariasis), was studied using a polyphasic approach. Cells of the isolate were rod-shaped and stained Gram-negative. A comparison of the 16S rRNA gene sequence of this organism with sequences of type strains of the most closely related species clearly showed an allocation to the genus Chryseobacterium, with the highest sequence similarities (all 97.9 %) to Chryseobacterium jejuense JS17-8(T), C. indologenes ATCC 29897(T), C. arthrosphaerae CC-VM-7(T) and C. aquifrigidense CW9(T). 16S rRNA gene sequence similarities to type strains of other Chryseobacterium species were below 97.5 %. The fatty acid profile of strain R4-1A(T) included the major fatty acids iso-15 : 0, summed feature 4 (comprising iso-15 : 0 2-OH and/or 16 : 1ω7c), iso-17 : 1ω9c and iso-17 : 0 3-OH. DNA-DNA hybridizations with C. jejuense KACC 12501(T), C. indologenes CCUG 14556(T), C. arthrosphaerae CC-VM-7(T) and C. aquifrigidense KCTC 12894(T) resulted in relatedness values of 38.3 % (reciprocal 30.5 %), 29.4 % (32.1 %), 23.2 % (37.2 %) and 29.5 % (47.1 %), respectively. These results and the differentiating biochemical and chemotaxonomic properties show that strain R4-1A(T) represents a novel species, for which the name Chryseobacterium culicis sp. nov. is proposed. The type strain is R4-1A(T) (=LMG 25442(T) =CCM 7716(T)).


Assuntos
Chryseobacterium/classificação , Chryseobacterium/isolamento & purificação , Culex/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Chryseobacterium/genética , Chryseobacterium/fisiologia , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Trato Gastrointestinal/microbiologia , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Filogenia , Pigmentos Biológicos/biossíntese , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
9.
J Evol Biol ; 21(5): 1220-6, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18636974

RESUMO

Viviparity is reported for Gegeneophis seshachari (Gymnophiona: Caeciliidae) from a gravid female containing four oviductal foetuses. The oviducts are highly vascularized and contain patches of thickened, layered tissue similar to foetal gut contents. Gegeneophis seshachari probably resemble other viviparous caecilians in having foetuses that ingest thickened oviduct lining using specialized deciduous teeth. This is the first report of viviparity in Asian amphibians and Indo-Seychellean caeciliids. Gegeneophis is the only caecilian genus known to include oviparous and viviparous species, and G. seshachari is the smallest known viviparous caecilian. Phylogenetic analysis of mitochondrial DNA sequences supports assignment of G. seshachari to a monophyletic Gegeneophis. Character optimization indicates that viviparity has evolved independently at least four times within Gymnophiona--a rate of incidence relative to the number of extant species that is higher than for other vertebrate groups except squamate reptiles. Our findings strengthen the proposal that caecilian reproduction demands further attention.


Assuntos
Anfíbios/fisiologia , Evolução Biológica , Viviparidade não Mamífera , Anfíbios/anatomia & histologia , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Feminino , Funções Verossimilhança , Modelos Genéticos , Filogenia , Alinhamento de Sequência , Análise de Sequência de DNA
10.
Braz J Microbiol ; 39(2): 397-404, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24031236

RESUMO

FLESH FLIES (DIPTERA: Sarcophagidae) are well known cause of myiasis and their gut bacteria have never been studied for antimicrobial activity against bacteria. Antimicrobial studies of Myroides spp. are restricted to nosocomial strains. A Gram-negative bacterium, Myroides sp., was isolated from the gut of adult flesh flies (Sarcophaga sp.) and submitted to evaluation of nutritional parameters using Biolog GN, 16S rRNA gene sequencing, susceptibility to various antimicrobials by disc diffusion method and detection of metallo ß-lactamase genes (TUS/MUS). The antagonistic effects were tested on Gram-negative and Gram-positive bacteria isolated from human clinical specimens, environmental samples and insect mid gut. Bacterial species included were Aeromonas hydrophila, A. culicicola, Morganella morganii subsp. sibonii, Ochrobactrum anthropi, Weissella confusa, Escherichia coli, Ochrobactrum sp., Serratia sp., Kestersia sp., Ignatzschineria sp., Bacillus sp. The Myroides sp. strain was resistant to penicillin-G, erythromycin, streptomycin, amikacin, kanamycin, gentamycin, ampicillin, trimethoprim and tobramycin. These strain showed antibacterial action against all bacterial strains except W. confusa, Ignatzschineria sp., A. hydrophila and M. morganii subsp. sibonii. The multidrug resistance of the strain was similar to the resistance of clinical isolates, inhibiting growth of bacteria from clinical, environmental and insect gut samples. The metallo ß-lactamase (TUS/MUS) genes were absent, and resistance due to these genes was ruled out, indicating involvement of other secretion machinery.

11.
Oncogene ; 25(47): 6336-44, 2006 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-16732329

RESUMO

Analyses of genome orthologs in cancer on the background of tumor heterogeneity, coupled with the recent identification that the tumor propagating capacity resides within a very small fraction of cells (the tumor stem cells-TSCs), has not been achieved. Here, we describe a strategy to explore genetic drift in the mitochondrial genome accompanying varying stem cell dynamics in epithelial ovarian cancer. A major and novel outcome is the identification of a specific mutant mitochondrial DNA profile associated with the TSC lineage that is drastically different from the germ line profile. This profile, however, is often camouflaged in the primary tumor, and sometimes may not be detected even after metastases, questioning the validity of whole tumor profiling towards determining individual prognosis. Continuing mutagenesis in subsets with a mutant mitochondrial genome could result in transformation through a cooperative effect with nuclear genes - a representative example in our study is a tumor suppressor gene viz. cAMP responsive element binding binding protein. This specific profile could be a critical predisposing step undertaken by a normal stem cell to overcome a tightly regulated mutation rate and DNA repair in its evolution towards tumorigenesis. Our findings suggest that varying stem cell dynamics and mutagenesis define TSC progression that may clinically translate into increasing tumor aggression with serious implications for prognosis.


Assuntos
Análise Mutacional de DNA , DNA Mitocondrial/genética , DNA de Neoplasias/genética , Perfilação da Expressão Gênica , Células-Tronco Neoplásicas/metabolismo , Neoplasias Ovarianas/patologia , Adenocarcinoma Papilar/genética , Adenocarcinoma Papilar/patologia , Substituição de Aminoácidos , Ascite/genética , Ascite/patologia , Proteína de Ligação a CREB/genética , Linhagem Celular Transformada/química , Linhagem Celular Transformada/patologia , Linhagem da Célula , Núcleo Celular/química , Células Clonais/química , Células Clonais/ultraestrutura , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/patologia , Cistadenocarcinoma Seroso/secundário , Cistadenoma/genética , Cistadenoma/patologia , Reparo do DNA , Células-Tronco de Carcinoma Embrionário , Evolução Molecular , Feminino , Genes Supressores de Tumor , Mutação em Linhagem Germinativa , Humanos , Mutagênese , Mutação de Sentido Incorreto , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/patologia , Mutação Puntual
12.
J Mol Biol ; 190(4): 635-8, 1986 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-3537317

RESUMO

Since the substrate binding domain of the large proteolytic fragment of Escherichia coli DNA polymerase I has been shown to interact with the B forms of DNA, we have studied the ability of this enzyme to recognize structures other than the B form. The polymerase activity has been used to evaluate the degree of recognition of the B and Z forms of DNA. The Z form was found to promote less activity, indicating the probable inability of the polymerase to move along the conformationally rigid form of the template. The present study indicates that the Z-DNA found in vivo may have a role in the control of replication.


Assuntos
DNA Polimerase I/metabolismo , DNA Bacteriano , Conformação de Ácido Nucleico , DNA Bacteriano/metabolismo , Escherichia coli/enzimologia , Especificidade por Substrato , Moldes Genéticos
13.
J Mol Biol ; 193(1): 201-11, 1987 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-3035193

RESUMO

pBR322 form V DNA is a highly torsionally strained molecule with a linking number of zero. We have used sequence-specific DNA methylases as probes for B-DNA in this molecule, exploiting the inability of methylases to methylate single-stranded DNA and Z-DNA, both of which are known to occur in form V DNA. Some sequences in form V DNA were shown to be totally in the B-form, others were totally in an altered, unmethylatable conformation, while still other sites appeared to exist partly in altered and partly in normal B-conformation. Some potential Z-forming sequences (alternating pyrimidine/purine) of less than seven base-pairs were not in the Z conformation in form V DNA, whereas others did adopt an altered structure, indicating a modulating influence of flanking sequences. Furthermore, regions of imperfect alternating pyrimidine/purine structure were sometimes capable of adopting an altered structure. In addition, some regions of altered structure had no apparent Z-forming sequences, nor were they in polypurine stretches, which have also been proposed to form left-handed DNA. These non-B-DNA conformations may represent novel left-handed helical structures or sequences that become single stranded under torsional strain. Long regions of either altered (unmethylatable) DNA or B-DNA were not always observed. In fact, one region showed three transitions between B-like DNA and altered structure within 26 base-pairs.


Assuntos
DNA Bacteriano , Escherichia coli/análise , Conformação de Ácido Nucleico , Sequência de Bases , DNA (Citosina-5-)-Metiltransferases , Enzimas de Restrição do DNA , Marcadores Genéticos , Metilação , Plasmídeos
14.
Indian J Med Microbiol ; 33(2): 231-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25865973

RESUMO

INTRODUCTION: Class1 integrons are one of the prevalent mechanisms of antibiotic resistance gene transfer in Gram-negative organisms, but their prevalence and role in the spread of antibiotic resistance genes in methicillin-resistant Staphylococcus aureus (MRSA) is unexplored. The purpose of this study was to investigate the prevalence of class 1 integrons in clinical isolates of MRSA. MATERIALS AND METHODS: Total 143 MRSA isolates obtained from two different cities in India (Pune and Mumbai) were characterized by biochemical tests, and the antibiotic sensitivity was performed using the Clinical and Laboratory Standards Institute (CLSI) guidelines. The presence of class 1 integrons, sul1/qacE0Δ1 region of class 1 integron and mecA gene among these isolates was determined by polymerase chain reaction (PCR). RESULTS: All 143 isolates were mecA positive and coagulase-positive. Overall, 71% of the MRSA isolates carried class 1 integrons; 58% (45/77) of the isolates obtained from Mumbai and 85% (56/66) of the isolates from Pune carried class 1 integrons. In all, 39% of these isolates carried sul1/qacEΔ1 region, thus confirming the association of class 1 integrons with antibiotic resistance genes. Along with ß-lactam antibiotics the MRSA isolates were resistant to several other antibiotics, with resistance to erythromycin, ciprofloxacin and trimethoprim-sulfamethoxazole being observed in 75%, 66% and 60% of the isolates, respectively. CONCLUSION: To the best of our knowledge, this is the first report of class 1 integrons in MRSA isolates from India. The study provides insights into the prevalence of a novel mechanism adapted by MRSA for the propagation of antibiotic resistance genes.


Assuntos
Integrons , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Antibacterianos/farmacologia , Cidades , DNA Bacteriano/genética , Humanos , Índia/epidemiologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Prevalência
15.
Insect Biochem Mol Biol ; 31(12): 1165-71, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11583929

RESUMO

Hexokinase coding DM1 and DM2 sequences were obtained from genomic DNA of a Drosophila melanogaster cell line by PCR amplification strategy. Both the sequences were found to encode an enzyme with a molecular weight of 50,000 Da. Amino acid sequence alignment of DM1 and DM2 shows approximately 45% homology with yeast and human hexokinases. The sequences also indicated the presence of conserved amino acid residues and motifs that are present in mammalian hexokinases and are involved in the binding of different substrates. Southern blot analysis suggests that the D. melanogaster genome contain a single copy of DM1 and DM2 sequences. Northern analysis indicates DM1 is expressed as more than one transcript in adult as well as in the D.Mel2 cell line. DM2 is expressed as a single transcript in adult flies. Expression levels for DM1 and DM2 encoded message were found to be similar in different stages of development as seen by RT-PCR. The biotechnological significance of these sequences in metabolic engineering of cells is discussed.


Assuntos
Drosophila melanogaster/enzimologia , Hexoquinase/genética , Sequência de Aminoácidos , Animais , Linhagem Celular , Clonagem Molecular , Drosophila melanogaster/genética , Expressão Gênica , Genes de Insetos , Humanos , Isoenzimas/genética , Dados de Sequência Molecular , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
16.
J Biosci ; 25(4): 361-6, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11120588

RESUMO

Mosquitoes are vectors for the transmission of many human pathogens that include viruses, nematodes and protozoa. For the understanding of their vectorial capacity, identification of disease carrying and refractory strains is essential. Recently, molecular taxonomic techniques have been utilized for this purpose. Sequence analysis of the mitochondrial 16S rRNA gene has been used for molecular taxonomy in many insects. In this paper, we have analysed a 450 bp hypervariable region of the mitochondrial 16S rRNA gene in three major genera of mosquitoes, Aedes, Anopheles and Culex. The sequence was found to be unusually A+T rich and in substitutions the rate of transversions was higher than the transition rate. A phylogenetic tree was constructed with these sequences. An interesting feature of the sequences was a stretch of Ts that distinguished between Ae-des and Culex on the one hand, and Anopheles on the other. This is the first report of mitochondrial rRNA sequences from these medically important genera of mosquitoes.


Assuntos
Culicidae/genética , RNA Ribossômico 16S/genética , RNA/genética , Animais , Sequência de Bases , Evolução Molecular , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , RNA Mitocondrial , Análise de Sequência de DNA , Especificidade da Espécie
17.
In Vitro Cell Dev Biol Anim ; 38(5): 262-4, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12418922

RESUMO

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.


Assuntos
Linhagem Celular , Mariposas/embriologia , Animais , Baculoviridae/fisiologia , Técnicas de Cultura de Células/métodos , Meios de Cultura , Embrião não Mamífero/citologia , Mariposas/citologia , Mariposas/parasitologia , Mariposas/virologia , Nucleopoliedrovírus/fisiologia
18.
Indian J Med Res ; 115: 189-93, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12362558

RESUMO

BACKGROUND & OBJECTIVES: Lepidopteran cell cultures and baculovirus expression vector systems are becoming popular due to their potential applications in biotechnology especially for the expression of foreign proteins. Efforts were made to develop new, indigenous, cell lines from Bombyx mori larvae and pupae. METHODS: Eight to ten B. mori larvae and 10-12 pupae were surface sterilized, dissected and ovaries were removed aseptically. Ovaries were chopped finely, washed and suspended in growth medium. When the cells formed monolayers, they were subcultured and experiments were carried out. RESULTS: Two new cell lines from larval and pupal ovaries of B. mori were established in Grace's insect tissue culture medium supplemented with 20 per cent FBS (foetal bovine serum). The larval cell line consisted predominantly of epithelial-like cells (98.31%), whereas the pupal cell line had a mixed cell population of epithelial-like (71.8%) and fibroblast-like cells (27.8%). Karyology indicated a typical lepidopteran pattern in both the cell lines and had chromosome numbers ranging from 35 to 150 and 60 to 180 for larval and pupal ovaries respectively. Four-fold increase in cell number was observed in these cell lines in 7 days. Both the cell lines were found susceptible to B. mori multiple nucleopolyhedrovirus and Autographa californica multiple nucleopolyhedrovirus, but not to Helicoverpa armigera single nucleopolyhedrovirus and Spodoptera litura multiple nucleopolyhedrovirus. INTERPRETATION & CONCLUSION: These well characterized cell lines may be of immense application in biotechnology and medicine for the production of biologically active recombinant proteins to use in vaccine studies as well as in therapeutic applications.


Assuntos
Bombyx/citologia , Linhagem Celular , Nucleopoliedrovírus/fisiologia , Animais , Bombyx/crescimento & desenvolvimento , Bombyx/virologia , Feminino , Ovário/embriologia
19.
Acta Virol ; 45(5-6): 305-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12083330

RESUMO

Chikungunya (CHIK) virus is prevalent throughout Southeast Asia and Africa. It has caused numerous large outbreaks in India. No active or passive surveillance has been carried out since the last epidemic occurring in 1971. During a recent outbreak of Dengue (DEN)-like illness in eastern India, Aedes aegypti mosquitoes collected from the affected area were positive for CHIK virus. Evidence of dual infection with CHIK and DEN typel virus was also obtained. A widely circulating low-virulent CHIK virus is a possible explanation for the epidemiological pattern of the CHIK virus disease in this region.


Assuntos
Aedes/virologia , Vírus Chikungunya/isolamento & purificação , Aedes/imunologia , Animais , Anticorpos Monoclonais , Encéfalo/virologia , Vírus Chikungunya/genética , Culicidae/virologia , Vírus da Dengue/imunologia , Feminino , Humanos , Índia/epidemiologia , Camundongos , Reação em Cadeia da Polimerase , Dengue Grave/patologia
20.
Indian J Exp Biol ; 40(1): 69-73, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12561972

RESUMO

A new cell line from the larval hemocytes of H. armigera was established in Grace's medium modified by adding lactalbumin hydrolysate and yeastolate (3.3g/l), and supplemented with fetal bovine serum (20%). The cell line was designated as NIV-HA-1195. The cell population at P-78 consisted mainly of epithelial-like cells (89.36%), fibroblast-like cells (8.31%) and giant cells (2.13%). The population doubling time was 96hr at P-8, 60hr at P-43. The chromosome number ranged from 45 to 200. The cell line is susceptible to the baculoviruses, Autographa californica nucleopolyhedrovirus (AcNPV), Spodoptera litura NPV and the homologous HaNPV. Isoenzyme profile and results of 16S rRNA heteroduplex analysis clearly indicated the species specificity of the new cell line.


Assuntos
Baculoviridae/fisiologia , Hemócitos/virologia , Mariposas/citologia , Animais , Divisão Celular , Linhagem Celular , Espaço Extracelular/virologia , Glucosefosfato Desidrogenase/análise , Análise Heteroduplex , Isocitrato Desidrogenase/análise , L-Lactato Desidrogenase/análise , Larva/citologia , Malato Desidrogenase/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA