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111.
Mi?osz A. Mazur 《ZooKeys》2016,(554):87-118
The genus Rasilinus
gen. n. is described (type species Rasilinus
tchambicus sp. n.). Nine new species: Rasilinus
bicolor
sp. n., Rasilinus
bifurcatus
sp. n., Rasilinus
bimaculatus
sp. n., Rasilinus
grandidens
sp. n., Rasilinus
longulus
sp. n., Rasilinus
subgemellus
sp. n., Rasilinus
subnodulus
sp. n., Rasilinus
tchambicus
sp. n., Rasilinus
virgatus
sp. n. are described from New Caledonia. Illustrations of the external morphology, male and female terminalia, dorsal habitus colour photographs of the adults, key to species and distribution map of the new genus Rasilinus are provided. 相似文献
112.
Influence of low temperature on productivity, proteome and protein phosphorylation of CHO cells. 总被引:6,自引:0,他引:6
Proliferation of mammalian cells can be controlled by low cultivation temperature. However, depending on cell type and expression system, varying effects of a temperature shift on heterologous protein production have been reported. Here, we characterize growth behavior and productivity of the Chinese hamster ovary (CHO) cell line XM111-10 engineered to synthesize the model-product-secreted alkaline phosphatase (SEAP). Shift of cultivation temperature from 37 degrees C to 30 degrees C caused a growth arrest mainly in the G1 phase of the cell cycle concomitant with an up to 1.7-fold increase of specific productivity. A low temperature cultivation provided 3.4 times higher overall product yield compared to a standard cultivation at 37 degrees C. The cellular and molecular mechanisms underlying the effects of low temperature on growth and productivity of mammalian cells are poorly understood. Separation of total protein extracts by two-dimensional gel electrophoresis showed altered expression levels of CHO-K1 proteins after decrease in cultivation temperature to 30 degrees C. These changes in the proteome suggest that mammalian cells respond actively to low temperature by synthesizing specific cold-inducible proteins. In addition, we provide the first evidence that the cold response of mammalian cells includes changes in postranslational protein modifications. Two CHO proteins were found to be phosphorylated at tyrosine residues following downshift of cultivation temperature to 30 degrees C. Elucidating cellular events during cold exposure is necessary for further optimization of host-cell lines and expression systems and can provide new strategies for metabolic engineering. 相似文献
113.
This study was performed to investigate the association between interferon (IFN)-gamma single nucleotide polymorphism (SNP) and susceptibility for psoriasis vulgaris. DNA from 78 patients with psoriasis vulgaris (54 patients with type I psoriasis, 24 with type II psoriasis) and 74 healthy volunteers was investigated. IFN-gamma promoter gene SNP in position 874 was evaluated by polymerase chain reaction with sequence-specific primers (PCR-SSP) and the results were compared between a group of psoriatic patients, divided into early onset of psoriasis (type I) and late onset of psoriasis (type II) subgroups, and healthy control subjects. A significant difference in the genotype frequencies between psoriasis patients and healthy controls was found (p < 0.02) and no significant differences were observed analyzing subsets of psoriatic patients (gender, type of disease) also in carriage and allele frequencies. The results suggest that IFN-gamma polymorphism is associated with susceptibility to psoriasis vulgaris. 相似文献
114.
Comparative molecular surface analysis (CoMSA) with robust IVE-PLS variable elimination if tested for the benchmark CBG steroid
series provides highly predictive RI 3D QSAR models, but failed however to model the activity of sulforaphane (SP) activators
of quinone reductase. The application of the SP poses obtained from multipose molecular docking to model the RD IVE-PLS CoMSA
resulted in a predictive form. This model indicated lipophilic potential as the activity determinant. The individual molecular
surface areas of the highest contribution to the SP activity was identified and visualized by CoMSA contour plots. 相似文献
115.
Tian X Mishra RK Switzer AG Hu XE Kim N Mazur AW Ebetino FH Wos JA Crossdoersen D Pinney BB Farmer JA Sheldon RJ 《Bioorganic & medicinal chemistry letters》2006,16(17):4668-4673
The design and synthesis of a series of potent 1,3,4-trisubstituted-2-oxopiperazine based MC4 agonists are described. The tripeptidomimetic analogs (12a,b and 23) and the dipeptidomimetic 27 displayed single-nanomolar binding affinity and agonist potency for MC4R and excellent selectivity for MC4R relative to MC1R. 相似文献
116.
Allan Mazur 《Evolution》2010,3(4):629-632
Half of US respondents to the 2006 General Social Surveys did not believe in the “Big Bang” origin of the universe; they were
closely correlated with those who did not believe in human evolution. Religious fundamentalism is the major predictor of both
disbeliefs. Low education and political conservatism have lesser but independent effects. The notion of continental drift
(plate tectonics) faces relatively little opposition from religious fundamentalists, and according to survey responses, its
validity is widely accepted, more so than the fact of a heliocentric solar system. 相似文献
117.
Cellulose, a very abundant extracellular polysaccharide, is synthesized in a finely tuned process that involves the activity of glycosyl-transferases and hydrolases. The cellulose microfibril consists of bundles of linear β-1,4-glucan chains that are synthesized inside the cell; however, the mechanism by which these polymers traverse the cell membrane is currently unknown. In Gram-negative bacteria, the cellulose synthase complex forms a trans-envelope complex consisting of at least four subunits. Although three of these subunits account for the synthesis and translocation of the polysaccharide, the fourth subunit, BcsZ, is a periplasmic protein with endo-β-1,4-glucanase activity. BcsZ belongs to family eight of glycosyl-hydrolases, and its activity is required for optimal synthesis and membrane translocation of cellulose. In this study we report two crystal structures of BcsZ from Escherichia coli. One structure shows the wild-type enzyme in its apo form, and the second structure is for a catalytically inactive mutant of BcsZ in complex with the substrate cellopentaose. The structures demonstrate that BcsZ adopts an (α/α)(6)-barrel fold and that it binds four glucan moieties of cellopentaose via highly conserved residues exclusively on the nonreducing side of its catalytic center. Thus, the BcsZ-cellopentaose structure most likely represents a posthydrolysis state in which the newly formed nonreducing end has already left the substrate binding pocket while the enzyme remains attached to the truncated polysaccharide chain. We further show that BcsZ efficiently degrades β-1,4-glucans in in vitro cellulase assays with carboxymethyl-cellulose as substrate. 相似文献
118.
The aim of the study was to define the changes of the characteristics of physiological postural tremor under conditions of increasing fatigue and lack of sleep during prolonged military training (survival). The subjects of the study were 15 students of the Polish Air Force Academy in Dęblin. The average age was 19.9±1.3 years. During the 36-hour-long continuous military training (survival) the subjects were deprived of sleep. Four tremor measurements were carried out for each of the subjects: Day 1 – morning, after rest (measurement 0); Day 2 – morning, after overnight physical exercise (measurement 1); afternoon, after continuous sleep deprivation (measurement 2); Day 3 – morning, after a full night sleep (measurement 3). The accelerometric method using an acceleration measuring kit was applied to analyse tremor. A significant difference between mean values of the index evaluating tremor power in low frequencies L2-4 in measurement 0 and measurement 3 was observed (p<0.01). No significant differences were found in mean values of index L10-20. Mean frequencies F2-4 differed significantly from each other (F2,42=4.53; p<0.01). Their values were 2.94±0.11, 2.99±0.9, 2.93±0.07 and 2.91±0.07 for successive measurements. A gradual, significant decrease of F8-14 was observed (F2,42=5.143; p<0.01). Prolonged sleep deprivation combined with performing tasks demanding constant physical effort causes long-lasting (over 24 hours) changes of the amplitude of low-frequency tremor changes. This phenomenon may significantly influence psychomotor performance, deteriorating the ability to perform tasks requiring movement precision. 相似文献
119.
The apparently anomalous flexibility of DNA on short length scales has attracted a lot of attention in recent years. We use atomic force microscopy (AFM) in solution to directly study the DNA bending statistics for small lengths down to one helical turn. The accuracy of experimental estimates could be improved due to a large data volume and a refined algorithm for image processing and measuring bend angles. It is found that, at length scales beyond two helical turns (7 nm), DNA is well described by the harmonic worm-like chain (WLC) model with the bending persistence length of 56 nm. Below this threshold, the AFM data are also described by the WLC model assuming that the accuracy of measured bend angles is limited by the physical width of the double helix. We conclude that the double helical DNA behaves as a uniform elastic rod even at very short length scales. Strong bends due to kinks, melting bubbles and other deviations from the WLC model are statistically negligible. 相似文献
120.
Guihua Lu Xiping Wang Junhua Liu Kun Yu Yang Gao Haiyan Liu Changgui Wang Wei Wang Guokui Wang Min Liu Guanfan Mao Binfeng Li Jianying Qin Mian Xia Junli Zhou Jingmei Liu Shuqin Jiang Hua Mo Jinteng Cui Nobuhiro Nagasawa Shoba Sivasankar Marc C. Albertsen Hajime Sakai Barbara J. Mazur Michael W. Lassner Richard M. Broglie 《Plant cell reports》2014,33(4):617-631