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A BAC library of 30,228 clones with an average insert size of 102 kb was constructed in the grass Brachypodium sylvaticum.
Brachypodium has a simple genome, similar in size and repetitive DNA content to that of rice, and is more closely related than rice both to the major temperate cereals wheat and barley, and to the forage grasses. The library represents 6.6 genome equivalents, implying a 99.9% probability of recovering any specific sequence. The library was arrayed onto two high-density colony filters, which were screened with heterologous DNA probes from rice chromosome nine and from syntenous regions of wheat, barley, maize and oat. The construction of Brachypodium BAC contigs revealed that synteny between rice, wheat and Brachypodium was largely maintained over several regions of rice chromosome nine. This suggests that Brachypodium will be a useful tool in the elucidation of gene content in agronomically important cereal crops, complementing rice as a grass genome model. 相似文献
163.
Honoré G. Ouattara Ban L. Koffi Germain T. Karou Abdourahamane Sangaré Sebastien L. Niamke Jacques K. Diopoh 《World journal of microbiology & biotechnology》2008,24(9):1753-1760
The role of bacilli in cocoa fermentation is not well known. Their potential of production of pectinolytic enzymes during
this process was evaluated. Bacillus growth was monitored and pectinolytic strains were screened for their use of pectin as sole carbon source. Effects of cocoa
fermentation parameters susceptible to influence on enzyme production were analysed. Among 98 strains isolated, 90 were positive
for pectin degradation and 80% of them presented detectable pectinolytic activities in submerged fermentation. Forty-eight
strains produced polygalacturonase (PG), 47 yielded pectin lyase (PL) and 23 strains produced both enzymes. Bacilli growth
was not significantly affected during fermentation. PL production was favoured by galactose, lactose, glucose as sugars, and
arginine, glutamine, cysteine and ammonium sulphate as nitrogen compounds. Pectin at low concentration (0.05%) and iron stimulated
PL production. It was strongly repressed by galacturonic acid (1%), and negatively affected by nitrogen starvation, zinc and
temperatures above 45°C. PL yield was very weak below pH 4.0 and in anaerobic conditions. PG production was weakened by sucrose
and cation depletion. It was increased slightly by cysteine, ammonium nitrate and nitrogen starvation and significantly above
40°C. PG synthesis was not affected by acidic pH (3.0–6.0) or oxygen availability. As fermentation products, lactate and acetate
lowered the production of both enzymes while ethanol had no effect. The high proportion of pectinolytic producers among the
strains studied and analysis of factors influencing pectinolytic enzymes production, suggest that Bacillus sp. is liable to produce at least one enzyme during cocoa fermentation. 相似文献
164.
Papa Makhona Niang Anthony Arguelles‐Arias Sebastien Steels Olivia Denies Jean‐Marc Nicaud Patrick Fickers 《Cell biology international》2020,44(2):651-660
In response to osmotic stress, the yeast Yarrowia lipolytica produces erythritol, a four‐carbon sugar alcohol, from erythrose‐P, an intermediate of the pentose phosphate pathway. Under non‐stressing conditions (isotonic environment), the produced erythritol is subsequently recycled into erythrose‐P that can feed the pentose phosphate pathway. Herein, gene YALI0F01584g was characterized as involved in the erythritol catabolic pathway. Several experimental evidences suggested that it encodes an erythrulose‐1P isomerase that converts erythrulose‐1P into erythrulose‐4P. On the basis of our previous reports and results gathered in this study with genetically modified strains, including ΔYALI0F01584g and ΔYALI0F01628g disrupted mutants, the entire erythritol catabolic pathway has been characterized. 相似文献
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Michael H Perlin Joelle Amselem Eric Fontanillas Su San Toh Zehua Chen Jonathan Goldberg Sebastien Duplessis Bernard Henrissat Sarah Young Qiandong Zeng Gabriela Aguileta Elsa Petit Helene Badouin Jared Andrews Dominique Razeeq Toni Gabaldón Hadi Quesneville Tatiana Giraud Michael E. Hood David J. Schultz Christina A. Cuomo 《BMC genomics》2015,16(1)
167.
The bypass of ZipA by overexpression of FtsN requires a previously unknown conserved FtsN motif essential for FtsA–FtsN interaction supporting a model in which FtsA monomers recruit late cell division proteins to the Z ring
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Assembly of the divisome in Escherichia coli occurs in two temporally distinct steps. First, FtsZ filaments attached to the membrane through interaction with FtsA and ZipA coalesce into a Z ring at midcell. Then, additional proteins are recruited to the Z ring in a hierarchical manner to form a complete divisome, activated by the arrival of FtsN. Recently, we proposed that the interaction of FtsA with itself competes with its ability to recruit downstream division proteins (both require the IC domain of FtsA) and ZipA's essential function is to promote the formation of FtsA monomers. Here, we tested whether overexpression of a downstream division protein could make ZipA dispensable, presumably by shifting the FtsA equilibrium to monomers. Only overexpression of FtsN bypassed ZipA and a conserved motif in the cytoplasmic domain of FtsN was required for both the bypass and interaction with FtsA. Also, this cytoplasmic motif had to be linked to the periplasmic E domain of FtsN to bypass ZipA, indicating that linkage of FtsA to periplasmic components of the divisome through FtsN was essential under these conditions. These results are used to further elaborate our model for the role of FtsA in recruiting downstream division proteins. 相似文献
168.
Diane Heiser Yee Sun Tan Ian Kaplan Brian Godsey Sebastien Morisot Wen-Chih Cheng Donald Small Curt I. Civin 《PloS one》2014,9(4)
Several individual miRNAs (miRs) have been implicated as potent regulators of important processes during normal and malignant hematopoiesis. In addition, many miRs have been shown to fine-tune intricate molecular networks, in concert with other regulatory elements. In order to study hematopoietic networks as a whole, we first created a map of global miR expression during early murine hematopoiesis. Next, we determined the copy number per cell for each miR in each of the examined stem and progenitor cell types. As data is emerging indicating that miRs function robustly mainly when they are expressed above a certain threshold (∼100 copies per cell), our database provides a resource for determining which miRs are expressed at a potentially functional level in each cell type. Finally, we combine our miR expression map with matched mRNA expression data and external prediction algorithms, using a Bayesian modeling approach to create a global landscape of predicted miR-mRNA interactions within each of these hematopoietic stem and progenitor cell subsets. This approach implicates several interaction networks comprising a “stemness” signature in the most primitive hematopoietic stem cell (HSC) populations, as well as “myeloid” patterns associated with two branches of myeloid development. 相似文献
169.
Dorota Boruszewska Ilona Kowalczyk-Zieba Katarzyna Piotrowska-Tomala Jean Sebastien Saulnier-Blache Tomas Acosta Dariusz Jan Skarzynski Izabela Woclawek-Potocka 《Reproductive biology》2013,13(1):100-103
The objective of the study was to examine which cultured endometrial cells are the source and which are the target for lysophosphatidic acid (LPA) in the bovine uterus. LPA concentration as well as mRNA and protein expressions of the enzymes responsible for LPA synthesis (phospholipase A2: PLA2, autotaxin: AX) were greater in epithelial than in stromal cells (P < 0.05). In turn, mRNA and protein expression of LPA receptor (LPAR1) was lower in epithelial than in stromal cells (P < 0.05). We suggest that LPA in bovine endometrium is produced mainly by epithelial cells and affects mostly stromal cells acting via LPAR1. 相似文献
170.
Frederic Cedrone Sebastien Niel Sanja Roca Tej Bhatnagar Nadra Ait-abdelkader Claudia Torre 《Biocatalysis and Biotransformation》2013,31(6):357-364
An efficient and genetically stable expression system for the directed evolution of epoxide hydrolase from Aspergillus niger (ANEH) has been constructed. Error prone polymerase chain reaction (PCR) with defined mutation rates was used to create biodiversity in two libraries of mutants. Screening for activity allowed the isolation of clones with improved properties. One of these clones shows an expression level 3.4 higher than the original wild type clone in E.?coli SG13009 and a 3.3 fold increased catalytic efficiency on 4-(p-nitrophenoxy)-1,2-epoxybutane. In addition, a screening assay for determining the enantioselectivity in the kinetic resolution of styrene oxide has been established using mass spectrometry. 相似文献