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961.
We here report the genomic organisation of the grey mouse lemur (Microcebus murinus) MHC class II DQ and DR region based on BAC clone analysis. The sequenced Mimu-MHC haplotype spans 343 kb and encompasses the genes TAP2, DOB, DQB, DQA, DRB, DRA, BTNL2 and a further BTNL gene. The DQ and DR genes of this haplotype are not duplicated. Mimu-DOB is not transcribed and represents a pseudogene due to deletions and premature stop codons. Analysis of BAC clone DNA, a cDNA
sample and eight genomic DNA samples suggests that Mimu-DRB, Mimu-DQA and Mimu-DQB are highly polymorphic with the majority of peptide-binding residues being affected by polymorphisms. In contrast, Mimu-DRA is moderately polymorphic, and the variable amino acid positions are not part of the peptide-binding region. Phylogenetic
analysis of Mimu-DQA and Mimu-DQB and other primate DQA and DQB genes indicates that duplication of DQA and DQB loci occurred in Anthropoidea after the split from Strepsirrhini. 相似文献
962.
Marco Camardo Leggieri Neus Planas Pont Paola Battilani Naresh Magan 《Mycotoxin Research》2011,27(1):29-35
The aim of this work was to evaluate the potential use of qualitative volatile patterns produced by Penicillium nordicum to discriminate between ochratoxin A (OTA) producers and non-producer strains on a ham-based medium. Experiments were carried
out on a 3% ham medium at two water activities (aw ; 0.995, 0.95) inoculated with P. nordicum spores and incubated at 25°C for up to 14 days. Growing colonies were sampled after 1, 2, 3, 7 and 14 days, placed in 30-ml
vials, sealed and the head space analysed using a hybrid sensor electronic nose device. The effect of environmental conditions
on growth and OTA production was evaluated based on the qualitative response. However, after 7 days, it was possible to discriminate
between strains grown at 0.995 aw, and after 14 days, the OTA producer and non-producer strain and the controls could be discriminated at both aw levels. This study suggests that volatile patterns produced by P. nordicum strains may differ and be used to predict the presence of toxigenic contaminants in ham. This approach could be utilised
in ham production as part of a quality assurance system for preventing OTA contamination. 相似文献
963.
Wiszniewski W Lewis RA Stockton DW Peng J Mardon G Chen R Lupski JR 《Human genetics》2011,129(3):319-327
Leber congenital amaurosis (LCA) is a clinically and genetically heterogeneous retinal dystrophy. The causes of LCA have been
unraveled partially at the molecular level. At least 14 genes have been reported that, when mutated, result in LCA. To understand
the roles of the known genes in LCA, a group of outbred subjects from 60 apparently either recessive families, with one or
more affected individuals, or isolated patients were evaluated. One affected individual from each family underwent comprehensive
mutational analysis by direct DNA sequencing of all coding regions and splice junctions of 13 LCA genes. Mutations were identified
in 70% of individuals. CEP290 made the largest contribution to the identified mutations, providing 43% of those mutant alleles. We identified seven families
in which affected individuals with two mutant alleles, sufficient to cause disease, had an additional mutation at a second
LCA locus. Our findings suggest that mutational load can be important to penetrance of the LCA phenotype. 相似文献
964.
The importance of a particular habitat to nearshore fishes can be best assessed by both diurnal and nocturnal sampling. To
determine diel differences in fish assemblages in nearshore eelgrass and understory kelp habitats, fishes were sampled diurnally
and nocturnally at six locations in western Prince William Sound, Alaska, in summer 2007. Abundance of fish between day and
night were similar, but species composition and mean size of some fish changed. Species richness and species diversity were
similar in eelgrass during the day and night, whereas in kelp, species richness and species diversity were greater at night
than during the day. In eelgrass, saffron cod (Eleginus gracilis) was the most abundant species during the day and night. In kelp, the most abundant species were Pacific herring (Clupea pallasii) during the day and saffron cod at night. Diel differences in fish size varied by species and habitat. Mean length of saffron
cod was similar between day and night in eelgrass but was greatest during the day in kelp. Pacific herring were larger at
night than during the day in kelp. Diel sampling is important to identity nearshore habitats essential to fish and help manage
fish stocks at risk. 相似文献
965.
Jianshe Wang Yingguo Bai Pengjun Shi Huiying Luo Huoqing Huang Jun Yin Bin Yao 《World journal of microbiology & biotechnology》2011,27(2):207-213
A xylanase gene, xynA4-2, was obtained from the genome sequence of thermoacidophilic Alicyclobacillus sp. A4 and expressed in Escherichia coli BL21 (DE3). xynA4-2 encodes a mature protein of 411 residues with a calculated molecular weight of 46.8 kDa. Based on the amino acid sequence
similarities (highest identity of 61%), the enzyme was confined into glycoside hydrolase family 10. The purified recombinant
XynA4-2 exhibited maximum activity at pH 6.2 and 55°C. The enzyme was stable over a broad pH range, retaining more than 90%
of the original activity at pH 5.8–12.0, 37°C for 1 h. The substrate specificity of XynA4-2 was relatively narrow, exhibiting
100, 93, and 35% of the relative activity towards birchwood xylan, oat spelt xylan, and wheat arabinoxylan, respectively.
Supplementation of XynA4-2 to mash caused the reduction of mash filtration rate (5.6%) and viscosity (4.0%). When combined
with the commercial glucanase from Sunson, higher reduction was detected in the filtration rate (12.0%) and viscosity (17.2%).
These favorable properties make XynA4-2 a good candidate in the brewing industry. 相似文献
966.
Hong Jun Choi Joo Bin Hong Jeong Joon Park Won-Jae Chi Mu-Chan Kim Yong-Keun Chang Soon-Kwang Hong 《Biotechnology and Bioprocess Engineering》2011,16(1):81-88
The agar degrading bacterial strain GNUM-08124 was isolated from Enteromorpha compressa collected in the East Sea of Korea by using a selective artificial sea water (ASW) agar plate containing agar as the sole carbon source. GNUM-08124 grows to produce a circular, smooth, yellow-colored, and raised colony. Its ability to hydrolyze agar was confirmed by staining the ASW agar plate with Lugol’s solution. In liquid culture, the cell density (A600) increased exponentially and reached a maximum level on the third day of cultivation. The specific agarase activity also increased in proportion to the cell density and reached maximum agarolytic activity on the third day. The 16S rRNA sequence of GNUM-08124 showed a close relationship to Micrococcus luteus (99.65%) and Micrococcus endophyticus (99.15%), which led us to assign it to the genus Micrococcus. Physiological studies indicated that optimal growth conditions were between 30 and 40°C, pH 4 and 7, using media containing between 5 and 10% NaCl (w/v), respectively. The GNUM-08124 strain was a grampositive, urease-positive, and catalase-positive bacterium. It could not hydrolyze gelatin, cellulose, xylan, or starch, but fermented a broader range of substrates, including Dglucose, D-galactose, D-fructose, D-lactose, D-trehalose, D-mannitol, D-melibiose, D-raffinose, D-xylose, methyl-α-D-glucopyranoside, N-acetyl-glucosamine, and xylitol, than those fermented by M. luteus or M. endophyticus, suggesting GNUM-08124 is a novel agar hydrolyzing microorganism belonging to Genus Micrococcus. Micrococcus sp. GNUM-08124 showed the highest agarase activity when it was cultured in ASW-YP medium supplemented with 0.4% glucose, but demonstrated lower activity in rich media (LB or TSB), in spite of superior cell growth, implying that agarase production is tightly regulated in an agar-dependent manner and repressed in rich conditions. 相似文献
967.
Sung-Ho Oh Juhee Ahn Do-Hyung Kang Hyeon-Yong Lee 《Marine biotechnology (New York, N.Y.)》2011,13(2):205-214
The effect of ultrasonic extraction on extraction yields, cytotoxicity, and anticancer activity of Spirulina maxima was investigated in this study. Optimal extraction conditions were determined as 60 kHz frequency at 60°C for 30 min with
120 W intensity, which resulted in 19.3% of extraction yields and 19.1% of cytotoxicity on normal human cells. Yields from
conventional water and ethanol extraction were 15.8% at 100°C and 8.3% at 80°C, respectively. It was found that the extracts
obtained by ultrasonic extraction process selectively inhibited the digestive-related cancer cell lines, such as human stomach
cancer cells, having 89% of the highest inhibition ratio and 4.5 of the highest selectivity. In adding 0.5 mg/mL of the extract,
human promyelocytic leukemia cells' cell differentiation was increased 1.72 times over that of the control. Expression level
of B cell lymphoma-2 from Hep3B cell was also effectively suppressed by the extract obtained at 60 kHz and 60°C, leading to
the inhibition of the early step of carcinogenesis. This work suggests that anticancer activity of the extracts is due to
water-soluble polysaccharides rather than proteins and is further supported by the result that the ultrasonification extraction
process can efficiently extract relatively intact polysaccharides rather than digesting the proteins in S. maxima by matrix assisted laser desorption ionization-time of flight and high performance size exclusion chromatography chromatogram
analyses. Therefore, ultrasonic extraction increases both extraction yield and the biological activity of S. maxima extracts, which might be useful as an alternative natural anticancer agent in the medical and food industries. 相似文献
968.
Riccardo De Santis Andrea Ciammaruconi Giovanni Faggioni Silvia Fillo Bernardina Gentile Elisabetta Di Giannatale Massimo Ancora Florigio Lista 《BMC microbiology》2011,11(1):60
Background
Brucellosis, a zoonosis caused by the genus Brucella, has been eradicated in Northern Europe, Australia, the USA and Canada, but remains endemic in most areas of the world. The strain and biovar typing of Brucella field samples isolated in outbreaks is useful for tracing back source of infection and may be crucial for discriminating naturally occurring outbreaks versus bioterrorist events, being Brucella a potential biological warfare agent. In the last years MLVA-16 has been described for Brucella spp. genotyping. The MLVA band profiles may be resolved by different techniques i.e. the manual agarose gels, the capillary electrophoresis sequencing systems or the microfluidic Lab-on-Chip electrophoresis. In this paper we described a high throughput system of MLVA-16 typing for Brucella spp. by using of the microfluidics technology. 相似文献969.
Alsaba F Raja Furqan Ali Inshad A Khan Abdul S Shawl Daljit S Arora Bhahwal A Shah Subhash C Taneja 《BMC microbiology》2011,11(1):54
Background
Boswellic acids are pentacyclic triterpenes, which are produced in plants belonging to the genus Boswellia. Boswellic acids appear in the resin exudates of the plant and it makes up 25-35% of the resin. β-boswellic acid, 11-keto-β-boswellic acid and acetyl-11-keto-β-boswellic acid have been implicated in apoptosis of cancer cells, particularly that of brain tumors and cells affected by leukemia or colon cancer. These molecules are also associated with potent antimicrobial activities. The present study describes the antimicrobial activities of boswellic acid molecules against 112 pathogenic bacterial isolates including ATCC strains. Acetyl-11-keto-β-boswellic acid (AKBA), which exhibited the most potent antibacterial activity, was further evaluated in time kill studies, postantibiotic effect (PAE) and biofilm susceptibility assay. The mechanism of action of AKBA was investigated by propidium iodide uptake, leakage of 260 and 280 nm absorbing material assays. 相似文献970.
ZINBA (Zero-Inflated Negative Binomial Algorithm) identifies genomic regions enriched in a variety of ChIP-seq and related
next-generation sequencing experiments (DNA-seq), calling both broad and narrow modes of enrichment across a range of signal-to-noise
ratios. ZINBA models and accounts for factors that co-vary with background or experimental signal, such as G/C content, and
identifies enrichment in genomes with complex local copy number variations. ZINBA provides a single unified framework for
analyzing DNA-seq experiments in challenging genomic contexts. 相似文献