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91.
In the past decade, algal waste has been used as useful natural resource for production of enormous range of products that have wide economical and commercial importance. Pectinases are group of enzymes that have wide commercial applications. Hence, current study was designed to utilize algal biomass for the production of pectinases using submerged (SmF) and solid state fermentation (SSF) techniques. Different algal sources including brown (Dictyopteris polypodioides, Sargassum wightii and Dictyopteris divaricata) and green algae (Ulva lactuca and Codium tomentosum) were used and U. lactuca was found to be the most suitable substrate. Several bacterial and fungal strains were screened and among them Bacillus licheniformis KIBGE-IB4 was selected based on maximum pectinase production. SmF and SSF were studied utilizing U. lactuca as a substrate and results revealed that enzyme production was favoured by SmF (2457?±?3.31?U?mg?1) as compared to SSF (1432?±?1.46?U?mg?1). Parametric optimization of pectinase production indicated that B. licheniformis KIBGE-IB4 requires 10.0?g L–1 U. lactuca as a biomass in the medium with a pH 7.0 when incubated at 37?°C for 24 hours. Likewise, production of pectinase using algal resource was also compared with that of the conventional agricultural biomass and it was observed that when U. lactuca was used, the selected bacterial isolate produced a higher yield of enzyme than sugarcane bagasse and rice husk. Hence, it is anticipated that algal biomass can be efficiently utilized as an environmental friendly bioresource for the production of industrially important hydrolytic enzymes.  相似文献   
92.
This study focussed on the effect of diabetes on the chaperone function of alpha-crystallin. The authors relied on diabetic rats with a wide range of plasma glucose levels and non-diabetic control rats to establish a possible relationship between severity of diabetes and alpha-crystallin chaperone activity. In addition, 52-56 and 63-69 year-old diabetic and non-diabetic human lenses were used to show whether diabetes affects alpha-crystallin chaperone activity in human lenses. Correlation between plasma glucose levels and loss of chaperone activity of the alphaL-crystallin fraction in diabetic rats indicated good correlation. The glycemic threshold, reported before for cataract development in diabetic rats, seems to be valid for the chaperone activity loss as well. Analysis of the human lens alphaL-crystallin showed lower chaperone activity in all the diabetic lenses than in the age-matched control lenses. In the 63-69 age group, the loss in chaperone activity due to diabetes was significantly larger than in the 52-56 age group suggesting a dominant effect of duration of diabetes.  相似文献   
93.
Azam SS  Zarina S 《Bioinformation》2012,8(5):239-242
Databases are integral part of bioinformatics and need to be accessed most frequently, thus downloading and updating them on a regular basis is very critical. The establishment of bioinformatics research facility is a challenge for developing countries as they suffer from inherent low-bandwidth and unreliable internet connections. Therefore, the identification of techniques supporting download and automatic synchronization of large biological database at low bandwidth is of utmost importance. In current study, two protocols (FTP and Bit Torrent) were evaluated and the utility of a BitTorren based peer-to-peer (btP2P) file distribution model for automatic synchronization and distribution of large dataset at our facility in Pakistan have been discussed.  相似文献   
94.
Plasmonics - The present work investigates the effect of geometrical parameters of 1D nanograting on surface plasmon resonance (SPR) and plasmonic bandgap (PBG). The use of plasmonic grating device...  相似文献   
95.
96.
The amino acid sequence of βI-globin chain from Sindhi Krait (Bungarus sindanus sindanus) was determined to study the molecular evolution among snakes. The hemoglobin was isolated from the red blood cells and was analyzed by ion-exchange chromatography (IEX). The crude globin was subjected to reversed phased-high performance liquid chromatography (RP-HPLC) using C4 column. The N-terminal sequences of intact globin chains and tryptic peptides were determined by Edman degradation in a pulsed liquid gas phase sequencer using an online Phenylthiohydantoin analyzer. Sindhi Krait is expected to express three hemoglobin components that are composed of βII, βI, αD and αA-globin chains, as apparent by IEX, RP-HPLC and N-terminal sequence analyses. Sequence alignment and phylogenetic analyses of βI globin chain from Sindhi Krait showed closest relationship with βI globin chain from Rattlesnake, Water snake and Indigo snake. Interestingly, comparison of primary sequence of βI globin chain of Sindhi Krait with human β chain revealed 63 % similarity along with the retention of all heme contact points. Variations among the two sequences were prominent at αβ contact points and in regions directly not important for function.  相似文献   
97.
The effect of Nilaparvata lugens (St?l) infestation duration and density on the host preference and performance of Anagrus nilaparvatae Pang et Wang, an egg parasitoid of rice planthoppers, was determined. The results showed that the parasitoid preferred N. lugens eggs on the plants infested with 10 gravid N. lugens females for 1 d to those plants infested with 10 gravid females for 2 or 3 d. It was also found to prefer N. lugens eggs on plants infested with 10 or 20 adult females after 24 h of infestation to those plants infested with 5 or 80 females. The parasitoid's offsprings had lower survival rates, fecundities, female ratios, indexes of capacity for population increase, and longer developmental durations on plants when they were infested with high N. lugens density (80 adult females per plant). However, the performance of the parasitoid on plants infested with low N. lugens density (5 female adults per plant) was similar to those on plants with intermediate N. lugens density (10 or 20 adult females per plant). Low preference of the parasitoid for N. lugens eggs on plants with heavy or light infestation levels may be correlated with low host suitability and detectability, respectively. The result implies an important role of herbivore-induced rice volatiles in the host preference of the parasitoid A. nilaparvatae, by which the parasitoid perceives the host and its suitability.  相似文献   
98.
It is now well-established that phospholipase D is transiently stimulated upon activation by G-protein-coupled and receptor tyrosine kinase cell surface receptors in mammalian cells. Over the last 5 years, a tremendous effort has gone to identify the major intracellular regulators of mammalian phospholipase D and to the cloning of two mammalian phospholipase D enzymes (phospholipase D1 and D2). In this chapter, we review the physiological function of mammalian phospholipase D1 that is synergistically stimulated by ADP ribosylation factor, Rho and protein kinase Cα. We discuss the function of this enzyme in membrane traffic, emphasising the possible integrated relationships between consumption of vesicles in regulated exocytosis, membrane delivery and constitutive membrane traffic.  相似文献   
99.
We have investigated the effects of two halogenoalkylamine drugs, dibenamine and phenoxybenzamine, on the stimulated phosphatidylinositol turnover that is produced by neurotransmitters and hormones which interact with receptors to bring about an increase in cell surface Ca2+ permeability. The phosphatidylinositol responses we have investigated were those evoked by muscarinic cholinergic stimuli (parotid gland and pancreas), by α-adrenergic stimuli (parotid gland, vas deferens smooth muscle), by pancreozymin or caerulein (pancreas), by phytohaemagglutinin (lymphocytes) and by either 5-hydroxytryptamine or elevation of the extracellular K+ concentration (ileum smooth muscle). Phenoxybenzamine inhibited the muscarinic cholinergic, α-adrenergic, 5-hydroxytryptamine and high K+ responses, but not the responses to phytohaemagglutinin and to pancreozymin (or caerulein). Dibenamine was less effective than phenoxybenzamine in inhibiting the α-adrenergic response and the high K+ response, and it did not inhibit the responses to muscarinic cholinergic stimuli, to 5-hydroxytryptamine or to the polypeptides. N,N-dimethyl-2-bromo-2-phenylethylamine (DMPEA) inhibited the α-adrenergic response, but not the response to muscarinic cholinergic stimulation. The specificity of DMPEA for the α-adrenergic response agrees with its postulated site of action at the noradrenaline-binding site of this receptor system, whereas dibenamine and phenoxybenzamine are less specific drugs which inhibit a variety of the ‘physiological’ responses of cells, including those to muscarinic cholinergic, H1-histaminergic, α-adrenergic and 5-hydroxytryptamine stimuli. Previously, we suggested that dibenamine and phenoxybenzamine might show a constant pattern of effects on the phosphatidylinositol responses evoked through different receptors, phenoxybenzamine being inhibitory and dibenamine without effect [Jafferji & Michell (1976) Biochem. J. 160, 163–169]. However, this pattern has not been sustained throughout the present study of a larger range of Ca2+-mobilising stimuli.  相似文献   
100.
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