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1.
Jyotsana Prakash Rakesh Sharma Subhasree Ray Shikha Koul Vipin Chandra Kalia 《Indian journal of microbiology》2018,58(2):127-137
Wastewaters are a rich source of nutrients for microorganisms. However, if left unattended the biodegradation may lead to severe environmental hazards. The wastewaters can thus be utilized for the production of various value added products including bioenergy (H2 and CH4). A number of studies have reported utilization of various wastewaters for energy production. Depending on the nature of the wastewater, different reactor configurations, wastewater and inoculum pretreatments, co-substrate utilizations along with other process parameters have been studied for efficient product formation. Only a few studies have reported sequential utilization of wastewaters for H2 and CH4 production despite its huge potential for complete waste degradation. 相似文献
2.
3.
Baseline frequency of sister-chromatid exchanges (SCE) in newborn lymphocytes and its relationship to in vivo aging in humans 总被引:1,自引:0,他引:1
Heparinised cord blood from newborns and peripheral venous blood from three other age groups of individuals (1-75 years) have been cultured in vitro to obtain baseline frequencies of SCE and to see if the frequency of baseline SCE in vitro varies as a function of aging in vivo. The results demonstrate an age-dependent variation in the frequency of SCEs. Although the SCE frequency was lowest (5.10/cell) in 1-5-year-old infants, a significantly higher (P less than 0.001) frequency (8.97/cell) was observed in the cord blood of newborns. In old age, the level of SCE also increased. The plausible reason(s) for such observations is discussed. 相似文献
4.
Requirement, uptake, and subcellular distribution of Na2 75SeO3 in the larvae of the insectC. cephalonica was investigated. That Se is well tolerated byC. cephalonica upto an added level of 2 ppm in the diet is suggested by the observed increase in body weight, total protein, and succinate dehydrogenase levels. Significant increases in the State 3 respiration ensued with Se supplementation up to 2 ppm in the mitochondrial oxidation of D-glycerol 1-phosphate, succinate and NADH, along with concomitant unaltered State 4 respiration, leading to enhanced RCR values. Maximal uptake of75Se was registered in the larvae maintained on basal diet when subjected to short-term exposure to 0.5 ppm75Se level. When exposure level was further increased up to 20 ppm, the observed decrease in the uptake of75Se suggested that Se status of larvae itself controlled the tissue uptake. Subcellular distribution pattern revealed maximal incorporation of75Se (cpm/g tissue) in the supernatant fraction, whereas, maximal specific75Se activity (cpm/mg protein) was associated with the mitochondrial fraction. Autoradiography of the soluble fractions indicated the presence of single selenoprotein in the larval group with short term 2 ppm75Se exposure. Inherent Se controls both the extent and the nature of distribution of mitochondrial75Se incorporation. Uptake of45Ca by the insect mitochondria was enhanced by dietary Se up to 2 ppm but was unaffected by addition ofin vitro 75Se in the medium. A more fundamental role for Se in the mitochondrial energy metabolism emerges from these studies. 相似文献
5.
Cell-bound cholinesterase enzyme activity is reported for the first time in the mycelium ofTrichoderma harzianum. This enzyme hydrolyzes both the acetylcholine and the butyryl thiocholine esters. TheK
m
andV
max
for choline ester are 0.69 mM and 1.0 nmol acid released min–1 g–1 protein. However, the thiocholine ester has aK
m
value of 2.2 mM andV
max
value of 3.33 nmol product formed min.–1 g–1 protein. The enzyme is inhibited by eserine, a true classical cholinesterase inhibitor. 相似文献
6.
The analysis of primary sequences from a protein sequence data base suggests that the sequences can be considered as examples
of constrained random fractals. Fractal dimensions of the positional distributions of the 20 residues along the chain have
been calculated. These fractal dimensions can be used as indices of intrinsic preferences of various residues. 相似文献
7.
Shikha Bakshi Maninder Kaur Arpana Verma Sadhna Sharma 《Journal of biochemical and molecular toxicology》2023,37(8):e23386
Drug-induced liver injury (DILI) is an adverse outcome of the currently used tuberculosis treatment regimen, which results in patient noncompliance, poor treatment outcomes, and the emergence of drug-resistant tuberculosis. DILI is primarily caused by the toxicity of the drugs and their metabolites, which affect liver cells, biliary epithelial cells, and liver vasculature. However, the precise mechanism behind the cellular damage attributable to first-line antitubercular drugs (ATDs), as well as the effect of toxicity on the cell survival strategies, is yet to be elucidated. In the current study, HepG2 cells upon treatment with a high concentration of ATDs showed increased perforation within the cell, cuboidal shape, and membrane blebbing as compared with control/untreated cells. It was observed that ATD-induced toxicity in HepG2 cells leads to altered mitochondrial membrane permeability, which was depicted by the decreased fluorescence intensity of the MitoRed tracker dye at higher drug concentrations. In addition, high doses of ATDs caused cell damage through an increase in reactive oxygen species production in HepG2 cells and a simultaneous reduction in glutathione levels. Further, high dose of isoniazid (50–200 mM), pyrazinamide (50–200 mM), and rifampicin (20–100 µM) causes cell apoptosis and affects cell survival during toxic conditions by decreasing the expression of potent autophagy markers Atg5, Atg7, and LC3B. Thus, ATD-mediated toxicity contributes to the reduced ability of hepatocytes to tolerate cellular damage caused by altered mitochondrial membrane permeability, increased apoptosis, and decreased autophagy. These findings further emphasize the need to develop adjuvant therapies that can mitigate ATD-induced toxicity for the effective treatment of tuberculosis. 相似文献
8.
Julie L Richards Johanna R Abend Michelle L Miller Shikha Chakraborty-Sett Stephen Dewhurst Linda E Whetter 《European journal of biochemistry》2003,270(10):2287-2294
CD40 is a receptor with numerous functions in the activation of antigen presenting cells (APCs), particularly dendritic cells (DC). Using phage display technology, we identified linear peptides containing a novel FPGN/S consensus sequence that enhances the binding of phage to a purified murine CD40-immunoglobulin (Ig) fusion protein (CD40-Ig), but not to Ig alone. To examine the ability the FPGN/S peptides to enhance adenoviral infection of CD40-positive cells, we used bifunctional peptides consisting of an FPGN-containing peptide covalently linked to an adenoviral knob-binding peptide (KBP). One of these, FPGN2-KBP, was able to enhance adenoviral infection of both murine and human DCs in a dose-dependent manner. FPGN2-KBP also improved infection of murine B cell blasts, a murine B lymphoma cell line (L10A), and immortalized human B cells. To demonstrate that enhancement of adenoviral infection depended on the presence of CD40, we analyzed infection of the breast cancer line, SKBR3, that does not express CD40 or the adenovirus cellular receptor, CAR. Infection of SKBR3 cells was enhanced by FPGN2-KBP following transient transfection with a plasmid vector that expresses murine CD40, but not when the cells were mock-transfected. In conclusion, we have isolated a peptide that binds to murine CD40, and promotes the uptake of adenoviruses into CD40-expressing cells of both murine and human origin, suggesting that it may have potential applications for antigen delivery to CD40-positive antigen-presenting cells. 相似文献
9.
K. Sudha Rani M. V. Swamy D. Sunitha D. Haritha G. Seenayya 《World journal of microbiology & biotechnology》1996,12(1):57-60
Two Clostridium thermocellum strains were improved for ethanol tolerance, to 5% (v/v), by gradual adaptation and mutation. The best mutant gave an ethanol yield of 0.37 g/g substrate, with a growth yield 1.5 times more than its parent. Accumulation of acids and reducing sugars by the mutant strain with 5% (v/v) ethanol was lower than that of the parent strain with 1.5% (v/v) ethanol. 相似文献
10.