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61.
Intrinsic disorder in proteins has been explored to study lack of structure-function aspects of many proteins. The current study focuses on coiled coils which are often linked to intrinsic disorder. We present a sequence level analysis of human coiled coils to find out if this is universally true for all coiled coils. When annotated coiled-coil regions were collected from UniProt and investigated with disorder prediction tools namely-IUPred and DISpro, three patterns were commonly observed-disordered coiled coils (DisCCs), ordered coiled coils (OCCs) and the last one having a disordered region outside the coiled-coil region (DOCCs). Differential enrichment in the gene ontology was seen in these three categories. We found that OCCs are enriched in structural components of the extracellular space including the fibrinogen complex and laminin complex. On the contrary, DisCCs were found to be exclusively over-represented in proteins involved in actin filament, lamellipodium, cell junction, macromolecule complexes, ciliary rootlet and nucleolus. DOCCs are found to be associated with many regulatory and adaptor functions including positive regulation of calcium ion transport via store-operated calcium channel activity, cytoskeletal adaptor activity etc. Other than the GO-based analysis, sequence level analysis showed that disordered coiled-coil regions bear a high proportion of low-complexity regions as compared to ordered coiled coils. The former also has a higher probability of forming a dimer as compared to the ordered counterpart. Our study shows that the in silico approach of mapping of disorder in or around coiled coils in other biological systems or organisms can be applied to understand and rationalize the mode of action of these dynamic motifs. 相似文献
62.
The fact that malaria is still an uncontrolled disease is reflected by the genetic organization of the parasite genome. Efforts to curb malaria should begin with proper understanding of the mechanism by which the parasites evade human immune system and evolve resistance to different antimalarial drugs. We have initiated such a study and presented herewith the results from the in silico understanding of a seventh chromosomal region of the malarial parasite Plasmodium falciparum encompassing the antigenic var genes (coding pfemp1) and the drug-resistant gene pfcrt located at a specified region of the chromosome 7. We found 60 genes of various functions and lengths, majority (61.67%) of them were performing known functions. Almost all the genes have orthologs in other four species of Plasmodium, of which P. chabaudi seems to be the closest to P. falciparum. However, only two genes were found to be paralogous. Interestingly, the drug-resistant gene, pfcrt was found to be surrounded by seven genes coding for several CG proteins out of which six were reported to be responsible for providing drug resistance to P. vivax. The intergenic regions, in this specified region were generally large in size, majority (73%) of them were of more than 500 nucleotide bp length. We also designed primers for amplification of 21 noncoding DNA fragments in the whole region for estimating genetic diversity and inferring the evolutionary history of this region of P. falciparum genome. 相似文献
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65.
Susanta Kumar Ghosh Satyanarayan Tiwari Kamaraju Raghavendra Tiruchinapalli Sundaraj Sathyanarayan Aditya Prasad Dash 《Journal of biosciences》2008,33(3):333-336
Sporozoites were detected in naturally infected sibling species of the primary rural vector Anopheles culicifacies complex in two primary health centres (PHCs) and a variant of the urban vector Anopheles stephensi in Mangalore city, Karnataka, south India while carrying out malaria outbreak investigations from 1998–2006. Sibling species
of An. culicifacies were identified based on the banding patterns on ovarian polytene chromosomes, and variants of An. stephensi were identified based on the number of ridges on the egg floats. Sporozoites were detected in the salivary glands by the
dissection method. Of the total 334 salivary glands of An. culicifacies dissected, 17 (5.08%) were found to be positive for sporozoites. Of the 17 positive samples, 11 were suitable for sibling
species analysis; 10 were species A (an efficient vector) and 1 was species B (a poor vector). Out of 46 An. stephensi dissected, one was sporozoite positive and belonged to the type form (an efficient vector). In malaria epidemiology this
observation is useful for planning an effective vector control programme, because each sibling species/variant differs in
host specificity, susceptibility to malarial parasites, breeding habitats and response to insecticides. 相似文献
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67.
NaCl salt stress induced changes in growth and enzyme activities in blackgram (Phaseolus mungo L.) seeds during germination were studied. A decrease in germination percentage, root length, shoot length, and fresh mass was noticed with an increase in NaCl concentration. With the increase in NaCl concentration and duration of stress proline content increased and catalase (CAT), peroxidase (POX) and polyphenol oxidase (PPO) activities decreased. 相似文献
68.
KR Rupesh PL PremKumar Vasanth V Shiva Kumar Seetharaman S Jayachandran 《BMC microbiology》2002,2(1):5-7
Background
Seeds of the legume plant Lathyrus sativus, which is grown in arid and semi arid tropical regions, contain Diamino Propionic acid (DAP). DAP is a neurotoxin, which, when consumed, causes a disease called Lathyrism. Lathryrism may manifest as Neurolathyrism or Osteolathyrism, in which the nervous system, and bone formation respectively, are affected. DAP ammonia lyase is produced by a few microorganisms such as Salmonella typhi, Salmonella typhimurium and Pseudomonas, and is capable of detoxifying DAP. 相似文献69.
Traditional taxonomy of hyphomycetes has been based on conidial morphology and development. In order to confirm species level
for the detection and identification of the entomopathogenic fungus, we analysed the species-specific fingerprints to investigate
molecular characteristics within isolates of six species and to resolve morphologically atypical isolates. The extent of fingerprint
profile observed by RAPD was sufficient to confirm the species level of all the isolates. The genetic similarity among morphologically
identified isolates of each species was considerably higher, allowing us to conclude that all the isolates are of same species.
These results establish a molecular framework for further taxonomic, phylogenetic and comparative biological investigations. 相似文献
70.
Pramod K. Dash † Beth A. Traxler ‡ Mitradas M. Panicker § David D. Hackney Edwin G. Minkley Jr 《Molecular microbiology》1992,6(9):1163-1172
The gene product of F tral is a bifunctional protein which nicks and unwinds the F plasmid during conjugal DNA transfer. Further biochemical characterization of the Tral protein reveals that it has a second, much lower, Km for ATP hydrolysis, in addition to that previously identified. Measurement of the single-stranded DNA-stimulated ATPase rate indicates that there is co-operative interaction between the enzyme monomers for maximal activity. Furthermore, 18O-exchange experiments indicate that Tral protein hydrolyses ATP with, at most, a low-level reversal of the hydrolytic step during each turnover. 相似文献