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991.
Khrenova M Domratcheva T Grigorenko B Nemukhin A 《Journal of molecular modeling》2011,17(7):1579-1586
The first biochemical and structural characterization of the full-length active photoreceptor BlrP1 from Klebsiella pneumoniae was recently reported by Barends et al. [Nature 459:1015–1018, (2009)]. The light-regulated catalytic function of its C-terminal c-di-guanosine monophosphate phosphodiesterase, the EAL (Glu-Ala-Leu)
domain, is activated by the N-terminal sensor of blue light using the flavin adenine dinucleotide (BLUF) domain. We performed
molecular dynamics simulations on the dimeric BlrP1 protein in order to examine the coupling regions that are presumably involved
in transmitting light-induced structural changes which occur in the BLUF domain to the EAL domain. According to the results
of simulations and an analysis of the hydrogen bonding between the respective polypeptide chains, the region containing the
site on the α3α4 loop of BLUF is responsible for communication between the photosensing and catalytic domains in the dimeric
BlrP1 protein. 相似文献
992.
993.
The currently spreading arbovirus epidemic is having a severe impact on human health worldwide. The two most common flaviviruses, dengue virus (DENV) and Zika virus (ZIKV), are transmitted through the same viral vector, Aedes spp. mosquitoes. Since the discovery of DENV in 1943, this virus has been reported to cause around 390 million human infections per year, approximately 500,000 of which require hospitalization and over 20,000 of which are lethal. The present DENV epidemic is primarily concentrated in Southeast Asia. ZIKV, which was discovered in 1952, is another important arthropod-borne flavivirus. The neurotropic role of ZIKV has been reported in infected newborns with microcephaly and in adults with Guillain-Barre syndrome. Despite DENV and ZIKV sharing the same viral vector, their complex pathogenic natures are poorly understood, and the infections they cause do not have specific treatments or effective vaccines. Therefore, this review will describe what is currently known about the clinical characteristics, pathogenesis mechanisms, and transmission of these two viruses. Better understanding of the interrelationships between DENV and ZIKV will provide a useful perspective for developing an effective strategy for controlling both viruses in the future. 相似文献
994.
Andreas Sjödin Kirsten Wissel Max Bylesjö Johan Trygg Stefan Jansson 《BMC plant biology》2008,8(1):61
Background
Genomic studies are routinely performed on young plants in controlled environments which is very different from natural conditions. In reality plants in temperate countries are exposed to large fluctuations in environmental conditions, in the case of perennials over several years. We have studied gene expression in leaves of a free-growing aspen (Populus tremula) throughout multiple growing seasons 相似文献995.
Background
Bacteriocins are very diverse group of antimicrobial peptides produced by a wide range of bacteria and known for their inhibitory activity against various human and animal pathogens. Although many bacteriocins are now well characterized, much information is still missing or is unavailable to potential users. The assembly of such information in one central resource such as a database would therefore be of great benefit to the exploitation of these bioactive molecules in the present context of increasing antibiotic resistance and natural bio-preservation need. 相似文献996.
Frances M Dupont 《BMC plant biology》2008,8(1):39
Background
By definition, amyloplasts are plastids specialized for starch production. However, a proteomic study of amyloplasts isolated from wheat (Triticum aestivum Butte 86) endosperm at 10 days after anthesis (DPA) detected enzymes from many other metabolic and biosynthetic pathways. To better understand the role of amyloplasts in food production, the data from that study were evaluated in detail and an amyloplast metabolic map was outlined. 相似文献997.
Davoud Nouri Inanlou Bagher Yakhchali Hossein Khanahmad Mossa Gardaneh Hesam Movassagh Reza Ahangari Cohan Mehdi Shafiee Ardestani Reza Mahdian Sirous Zeinali 《Biotechnology letters》2010,32(11):1615-1621
We have developed an integrase-defective lentiviral (LV) vector in combination with a gene-targeting approach for gene therapy
of β-thalassemia. The β-globin gene-targeting construct has two homologous stems including sequence upstream and downstream
of the β-globin gene, a β-globin gene positioned between hygromycin and neomycin resistant genes and a herpes simplex virus
type 1 thymidine kinase (HSVtk) suicide gene. Utilization of integrase-defective LV as a vector for the β-globin gene increased the number of selected clones
relative to non-viral methods. This method represents an important step toward the ultimate goal of a clinical gene therapy
for β-thalassemia. 相似文献
998.
The response to signals, including scent marks, from opposite-sex conspecifics can be affected by the nutritional state of
both the sender and receiver of these signals. Protein content of the diet affects how meadow voles (Microtus pennsylvanicus) respond to single scent marks, but it is unknown how it affects an individual’s response to the overlapping scent marks
of two donors (an over-mark). In experiment 1, we tested the hypothesis that protein content of the diet affects the amount
of time voles spend investigating the marks of the top- and bottom-scent donors of an over-mark. Males and females fed a 22%
protein diet spent more time investigating the scent mark of the top-scent donor than that of the bottom-scent donor; voles
fed 9% and 13% protein diets spent similar amounts of time investigating the top- and bottom-scent donors. In experiment 2,
we tested the hypothesis that protein content of the diet of the top- and bottom-scent donors affects the amount of time conspecifics
spend investigating their scent marks. Female voles spent more time investigating the mark of the top-scent male than that
of the bottom-scent male, independent of the differences in protein content of the diets of the top- and bottom-scent donors.
Male voles, however, spent more time investigating the top-scent female when she was fed a diet higher in protein content
than that of the bottom-scent female. Our results are discussed within the context of the natural history of voles. 相似文献
999.
Jing Zhang Ga Liao Chang Liu Lei Sun Yanyou Liu Yuhui Wang Zhou Jiang Zhengrong Wang 《Molecular biology reports》2011,38(1):349-354
Many reports have shown that the biologic rhythm could be altered due to mutations of circadian gene hClock or hPeriod, and
the mutations of circadian genes have some relationship with psychosis according to recent studies. A preliminary study has
been conducted to examine wether the T3111C single nucleotide polymorphism of the hClock gene or the length polymorphism of
the hPer3 gene is associated with the development of schizophrenia. The samples from schizophrenics (n = 148, male: 57.4%, female: 42.6%) and normal controls (n = 199, male: 59.3%, female: 40.7%) were examined. Allele frequencies of T3111C SNP of hClock were significantly different
between schizophrenics and controls (χ2 = 19.738, P < 0.05). Schizophrenics had a significantly higher frequency of the C allele compared with controls (OR = 2.613, 95% CI = 1.693–4.034).
On the other hand, there is no significant difference of allele frequencies of 18 exon of hper3 between schizophrenics and controls (χ2 = 0.192, P > 0.05). Our results suggest that the T3111C (RS1801260) polymorphism of hClock gene is associated with schizophrenia, but
it seems that the length polymorphism of 18 exon of hPer3 may not be associated with schizophrenia. It is important to address
of the relationship between circadian gene polymorphisms and dopamine functions in further study. 相似文献
1000.