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1.
Of 150 cultures capable of degrading petroleum at +6 degrees C, 40 strains growing in the liquid mineral nutrient medium containing petroleum (2%) as a sole source of carbon were selected. Of them, 13 cultures displaying a petroleum degradation rate exceeding 25% were selected. Abilities of these cultures and their associations to utilize fuel oil and its components--oils and benzene resins--were studied. The culture exhibiting degradation rates of fuel oil, its oils, benzene resins, and petroleum amounting to 17, 26, 10, and 51%, respectively, was selected. This culture can be used for cleanup of petroleum pollution under cold climatic conditions.  相似文献   
2.
The first population genetic study of hereditary disorders of the nervous system (HDNS) in Vladimir oblast was carried out. A total of 1,622,900 subjects, including 1,306,200 from the urban and 316,700 from the rural population, were tested. The population examined was characterized by virtually homogenous ethnic structure, with Russians constituting 95.76%. Pooled prevalence of HDNS in Vladimir oblast corresponded to the average prevalence for other Russian populations. Substantial differences between urban and rural populations in respect of the population load of HDNS and its nosological structure were not observed. A total of 22 nosological forms of HDNS were revealed, including thirteen autosomal dominant (193 families with 272 affected individuals), seven autosomal recessive (59 families with 66 affected individuals), and two X-linked (15 families with 17 affected individuals) diseases. The composition of the HDNS spectrum "nucleus" in Vladimir oblast displayed a number of differences from that in the majority of other populations examined. The HDNS in different regions of the area tested were characterized by different prevalence and spectrum. The data obtained may constitute a basis for regional registration of HDNS in Vladimir oblast.  相似文献   
3.
The first population genetic study of hereditary disorders of the nervous system (HDNS) in Vladimir oblast was carried out. A total of 1622900 subjects, including 1306200 from the urban and 316700 from the rural population, were tested. The population examined was characterized by virtually homogenous ethnic structure, with Russians constituting 95.76%. Pooled prevalence of HDNS in Vladimir oblast corresponded to the average prevalence for other Russian populations. Substantial differences between urban and rural populations in respect of the population load of HDNS and its nosological structure were not observed. A total of 22 nosological forms of HDNS were revealed, including thirteen autosomal dominant (193 families with 272 affected individuals), seven autosomal recessive (59 families with 66 affected individuals), and two X-linked (15 families with 17 affected individuals) diseases. The composition of the HDNS spectrum nucleus in Vladimir oblast displayed a number of differences from that in the majority of other populations examined. The HDNS in different regions of the area tested were characterized by different prevalence and spectrum. The data obtained may constitute a basis for regional registration of HDNS in Vladimir oblast.  相似文献   
4.
The cell wall of the model actinomycete Streptomyces coelicolor M145 has recently been shown to contain the novel glycopolymer teichulosonic acid. The major building block of this polymer is 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid (Kdn), suggesting initial clues about the genetic control of biosynthesis of this cell wall component. Here, through genome mining and gene knockouts, we demonstrate that the sco4879–sco4882 genomic region of S. coelicolor M145 is necessary for biosynthesis of teichulosonic acid. Specifically, mutants carrying individual knockouts of sco4879, sco4880 and sco4881 genes do not produce Kdn-containing glycopolymer and instead accumulate the minor cell wall component poly(diglycosyl 1-phosphate). Our studies provide evidence that this region is at least partly responsible for biosynthesis of Kdn, whereas flanking genes might control the other steps of teichulosonic acid formation.  相似文献   
5.
Genome sequencing projects have revealed a massive catalog of genes and astounding genetic diversity in a variety of organisms. We are now faced with the formidable challenge of assigning functions to thousands of genes, and how to use this information to understand how genes interact and coordinate cell function. Studies indicate that the majority of eukaryotic genes are dispensable, highlighting the extensive buffering of genomes against genetic and environmental perturbations. Such robustness poses a significant challenge to those seeking to understand the wiring diagram of the cell. Genome-scale screens for genetic interactions are an effective means to chart the network that underlies this functional redundancy. A complete atlas of genetic interactions offers the potential to assign functions to most genes identified by whole genome sequencing projects and to delineate a functional wiring diagram of the cell. Perhaps more importantly, mapping genetic networks on a large-scale will shed light on the general principles and rules governing genetic networks and provide valuable information regarding the important but elusive relationship between genotype and phenotype.  相似文献   
6.
Using small molecule probes to understand gene function is an attractive approach that allows functional characterization of genes that are dispensable in standard laboratory conditions and provides insight into the mode of action of these compounds. Using chemogenomic assays we previously identified yeast Crg1, an uncharacterized SAM-dependent methyltransferase, as a novel interactor of the protein phosphatase inhibitor cantharidin. In this study we used a combinatorial approach that exploits contemporary high-throughput techniques available in Saccharomyces cerevisiae combined with rigorous biological follow-up to characterize the interaction of Crg1 with cantharidin. Biochemical analysis of this enzyme followed by a systematic analysis of the interactome and lipidome of CRG1 mutants revealed that Crg1, a stress-responsive SAM-dependent methyltransferase, methylates cantharidin in vitro. Chemogenomic assays uncovered that lipid-related processes are essential for cantharidin resistance in cells sensitized by deletion of the CRG1 gene. Lipidome-wide analysis of mutants further showed that cantharidin induces alterations in glycerophospholipid and sphingolipid abundance in a Crg1-dependent manner. We propose that Crg1 is a small molecule methyltransferase important for maintaining lipid homeostasis in response to drug perturbation. This approach demonstrates the value of combining chemical genomics with other systems-based methods for characterizing proteins and elucidating previously unknown mechanisms of action of small molecule inhibitors.  相似文献   
7.
Conditional temperature-sensitive (ts) mutations are valuable reagents for studying essential genes in the yeast Saccharomyces cerevisiae. We constructed 787 ts strains, covering 497 (~45%) of the 1,101 essential yeast genes, with ~30% of the genes represented by multiple alleles. All of the alleles are integrated into their native genomic locus in the S288C common reference strain and are linked to a kanMX selectable marker, allowing further genetic manipulation by synthetic genetic array (SGA)-based, high-throughput methods. We show two such manipulations: barcoding of 440 strains, which enables chemical-genetic suppression analysis, and the construction of arrays of strains carrying different fluorescent markers of subcellular structure, which enables quantitative analysis of phenotypes using high-content screening. Quantitative analysis of a GFP-tubulin marker identified roles for cohesin and condensin genes in spindle disassembly. This mutant collection should facilitate a wide range of systematic studies aimed at understanding the functions of essential genes.  相似文献   
8.
Myocardial ischemia is characterized by reduced blood flow to cardiomyocytes, which can lead to acidosis. Acidosis decreases the calcium sensitivity and contractile efficiency of cardiac muscle. By contrast, skeletal and neonatal muscles are much less sensitive to changes in pH. The pH sensitivity of cardiac muscle can be reduced by replacing cardiac troponin I with its skeletal or neonatal counterparts. The isoform-specific response of troponin I is dictated by a single histidine, which is replaced by an alanine in cardiac troponin I. The decreased pH sensitivity may stem from the protonation of this histidine at low pH, which would promote the formation of electrostatic interactions with negatively charged residues on troponin C. In this study, we measured acid dissociation constants of glutamate residues on troponin C and of histidine on skeletal troponin I (His-130). The results indicate that Glu-19 comes in close contact with an ionizable group that has a pK(a) of ~6.7 when it is in complex with skeletal troponin I but not when it is bound to cardiac troponin I. The pK(a) of Glu-19 is decreased when troponin C is bound to skeletal troponin I and the pK(a) of His-130 is shifted upward. These results strongly suggest that these residues form an electrostatic interaction. Furthermore, we found that skeletal troponin I bound to troponin C tighter at pH 6.1 than at pH 7.5. The data presented here provide insights into the molecular mechanism for the pH sensitivity of different muscle types.  相似文献   
9.
Entomological Review - The paper summarizes new and literature data on the species composition, trophic relationships, and population dynamics of phyllophagous lepidopterans dominant on woody...  相似文献   
10.
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