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61.
62.
Adriana Gushterova Evgenia Vasileva-Tonkova Elitza Dimova Peter Nedkov Thomas Haertlé 《World journal of microbiology & biotechnology》2005,21(6-7):831-834
Summary The ability of actinomycete strains newly isolated from Antarctic soils to produce keratinolytic enzymes during growth on
sheep wool waste was investigated. The strains which displayed highest keratinase activity and identified as Streptomyces flavis 2BG (mesophilic) and Microbispora aerata IMBAS-11A (thermophilic) were selected for a more detailed analysis. The addition of starch to the growth medium affected
keratinase secretion by both strains. After 5 days of cultivation, a 6-fold increase in keratinase activity of strain 11A
was observed in the presence of 11 g starch/l and a 9-fold increase in keratinase activity of the strain 2BG in the presence
of 5 g starch/l. The results obtained showed that both newly isolated strains are very promising for effective processing
of native keratinous wastes. To our knowledge, this is the first report of Antarctic actinomycete strains that were able to
grow on keratin-containing wastes by producing keratinolytic enzymes. 相似文献
63.
Fani Koukouli Ioannis Paspaltsis Evgenia Salta Konstantinos Xanthopoulos Eftychia N. Koini Theodora Calogeropoulou Theodoros Sklaviadis 《朊病毒》2012,6(5):470-476
Prion diseases are fatal, neurodegenerative diseases characterized by the structural conversion of the normal, cellular prion protein, PrPC into an abnormally structured, aggregated and partially protease-resistant isoform, termed PrPSc. Although substantial research has been directed toward development of therapeutics targeting prions, there is still no curative treatment for the disease. Benzoxazines are bicyclic heterocyclic compounds possessing several pharmaceutically important properties, including neuroprotection and reactive oxygen species scavenging. In an effort to identify novel inhibitors of prion formation, several 5,7,8-trimethyl-1,4-benzoxazine derivatives were evaluated in vitro for their effectiveness on the expression levels of normal PrPC and its conversion to the abnormal isoforms of PrPSc in a scrapie-infected cell culture model. The most potent compound was 2-(4-methoxyphenyl)-5,7,8-trimethyl-3,4-dihydro-2H-1,4-benzoxazine, with a diminishing effect on the formation of PrPSc, thus establishing a class of compounds with a promising therapeutic use against prion diseases. 相似文献
64.
Differential regulation of serum- and glucocorticoid-inducible kinase 1 (SGK1) splice variants based on alternative initiation of transcription. 总被引:1,自引:0,他引:1
65.
Influence of the relaxation of mechanical tensions upon collective cell movements, shape formation, and expression patterns
of tissue-specific genes has been studied in Xenopus laevis embryos. We show that the local relaxation of tensile stresses within the suprablastoporal area (SBA) performed at the early-midgastrula
stage leads to a complete arrest of normal convergent cell intercalation towards the dorsal midline. As a result, SBA either
remains nondeformed or protrudes a strip of cells migrating ventralwards along one of the lateral lips of the opened blastopore.
Already, few minutes later, the tissues in the ventral lip vicinity undergo abnormal transversal contraction/longitudinal
extension resulting in the abnormal cell convergence toward ventral (rather than dorsal) embryo midline. Within a day, the
dorsally relaxed embryos acquire pharyngula-like shapes and often possess tail-like protrusions. Their antero-posterior and
dorso-ventral polarity, as well as expression patterns of pan-neural (Sox3), muscular cardiac actin, and forebrain (Otx2)
genes substantially deviate from the normal ones. We suggest that normal gastrulation is permanently controlled by mechanical
stresses within the blastopore circumference. The role of tissue tensions in regulating collective cell movements and creating
pharyngula-like shapes are discussed. 相似文献
66.
We developed a method to use any GFP-tagged construct in single-molecule super-resolution microscopy. By targeting GFP with small, high-affinity antibodies coupled to organic dyes, we achieved nanometer spatial resolution and minimal linkage error when analyzing microtubules, living neurons and yeast cells. We show that in combination with libraries encoding GFP-tagged proteins, virtually any known protein can immediately be used in super-resolution microscopy and that simplified labeling schemes allow high-throughput super-resolution imaging. 相似文献
67.
Danielle G Lemay David J Lynn William F Martin Margaret C Neville Theresa M Casey Gonzalo Rincon Evgenia V Kriventseva Wesley C Barris Angie S Hinrichs Adrian J Molenaar Katherine S Pollard Nauman J Maqbool Kuljeet Singh Regan Murney Evgeny M Zdobnov Ross L Tellam Juan F Medrano J Bruce German Monique Rijnkels 《Genome biology》2009,10(4):R43
Background
The newly assembled Bos taurus genome sequence enables the linkage of bovine milk and lactation data with other mammalian genomes.Results
Using publicly available milk proteome data and mammary expressed sequence tags, 197 milk protein genes and over 6,000 mammary genes were identified in the bovine genome. Intersection of these genes with 238 milk production quantitative trait loci curated from the literature decreased the search space for milk trait effectors by more than an order of magnitude. Genome location analysis revealed a tendency for milk protein genes to be clustered with other mammary genes. Using the genomes of a monotreme (platypus), a marsupial (opossum), and five placental mammals (bovine, human, dog, mice, rat), gene loss and duplication, phylogeny, sequence conservation, and evolution were examined. Compared with other genes in the bovine genome, milk and mammary genes are: more likely to be present in all mammals; more likely to be duplicated in therians; more highly conserved across Mammalia; and evolving more slowly along the bovine lineage. The most divergent proteins in milk were associated with nutritional and immunological components of milk, whereas highly conserved proteins were associated with secretory processes.Conclusions
Although both copy number and sequence variation contribute to the diversity of milk protein composition across species, our results suggest that this diversity is primarily due to other mechanisms. Our findings support the essentiality of milk to the survival of mammalian neonates and the establishment of milk secretory mechanisms more than 160 million years ago. 相似文献68.
Vanhooren V Dewaele S Kuro-O M Taniguchi N Dollé L van Grunsven LA Makrantonaki E Zouboulis CC Chen CC Libert C 《Aging cell》2011,10(6):1056-1066
We recently reported that N-glycosylation changes during human aging. To further investigate the molecular basis determining these alterations, the aging process in mice was studied. N-glycan profiling of mouse serum glycoproteins in different age groups of healthy C57BL/6 mice showed substantial age-related changes in three major N-glycan structures: under-galactosylated biantennary (NGA2F), biantennary (NA2), and core α-1,6-fucosylated -β-galactosylated biantennary structures (NA2F). Mice defective in klotho gene expression (kl/kl), which have a shortened lifespan, displayed a similar but accelerated trend. Interestingly, the opposite trend was observed in slow-aging Snell Dwarf mice (dw/dw) and in mice fed a calorically restricted diet. We also discovered that increased expression and activity of α-1,6-fucosyltransferase (FUT8) in the liver are strongly linked to the age-related changes in glycosylation and that this increased FUT8 and fucosylation influence IGF-1 signaling. These data demonstrate that the glycosylation machinery in liver cells is significantly affected during aging and that age-related increased FUT8 activity could influence the aging process by altering the sensitivity of the IGF-1R signaling pathway. 相似文献
69.
70.
Victoria Gesheva Erko Stackebrandt Evgenia Vasileva-Tonkova 《Current microbiology》2010,61(2):112-117
Isolate A-3 from Antarctic soil in Casey Station, Wilkes Land, was characterized for growth on hydrocarbons. Use of glucose or kerosene as a sole carbon source in the culture medium favoured biosynthesis of surfactant which, by thin-layer chromatography, indicated the formation of a rhamnose-containing glycolipid. This compound lowered the surface tension at the air/water interface to 27 mN/m as well as inhibited the growth of B. subtilis ATCC 6633 and exhibited hemolytic activity. A highly hydrophobic surface of the cells suggests that uptake occurs via a direct cell–hydrocarbon substrate contact. Strain A-3 is Gram-positive, halotolerant, catalase positive, urease negative and has rod–coccus shape. Its cell walls contained meso-diaminopimelic acid. Phylogenetic analysis based on comparative analysis of 16S rRNA gene sequences revealed that strain A-3 is closely related to Rhodococcus fascians with which it shares 100% sequence similarity. This is the first report on rhamnose-containing biosurfactant production by Rhodococcus fascians isolated from Antarctic soil. 相似文献