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101.
Ian T. Forrester Anthony C. Grabski Chittra Mishra Brian D. Kelley W. Nick Strickland Gary F. Leatham Richard R. Burgess 《Applied microbiology and biotechnology》1990,33(3):359-365
Summary Extracellular culture filtrates from ligninolytic cultures of the lignin-degrading basidiomycete Lentinula (syn. Lentinus) edodes (Berk.) Pegler contained one major peroxidase when grown on a commercial oak-wood substrate. The peroxidase was purified by polyethylenimine clarification, anion-exchange chromatography, and hydrophobic-interaction HPLC. The enzyme (MnP1) was a heme-iron protein with an apparent molecular weight of 44 600 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels and an isoelectric point of pH 3.2. The native enzyme had an absorption maximum at 407 nm, which shifted to 420 nm upon H2O2 addition. The pyridine-hemochrome-absorption spectrum indicated that one heme group was present per enzyme as protoporphyrin IX. N-terminal amino acid sequencing showed that MnP1 had higher sequence homology with manganese peroxidases than with lignin peroxidases reported from Phanerochaete chrysosporium. L. edodes MnP1 was capable of oxidizing lignin and lignin-model compounds in the presence of manganese and H2O2.On leave from the Department of Biochemistry, University of Otago, P. O. Box 56, Dunedin, New Zealand.Research carried out while a visiting scientist at the USDA Forest Products Laboratory from the National Chemistry Laboratory, Pune, India 41 1008
Offprint requests to: I. T. Forrester 相似文献
102.
BACKGROUND: The increased incidence of fungal diseases in humans is most likely due to indiscriminate use of broad-spectrum antibiotics and increased numbers of immunocompromised patients. Although Aspergillus species are ubiquitous and normally nonpathogenic, they can be opportunistic pathogens in immunocompromised individuals. CASE: A 22-year-old immunocompetent man presented with a gradually increasing subcutaneous swelling near the root of his nose for previous 6 months. The mass was soft to firm, solid, nontender and immobile. There was no superficial skin ulceration and no local signs of inflammation. Proptosis of the left eye was present without any visual impairment. An osteolytic lesion that was contiguous with the subcutaneous mass, with the opacities of both the fontal sinuses was observed radiographically. Fine needle aspiration cytology (FNAC) demonstrated presence of branching hyphae in the cytoplasm of multinucleated giant cells along with mixed inflammatory cells. The species was identified by culture in Sabouraud's agar with chloramphenicol and wet mount with lactophenol cotton blue stain. CONCLUSION: Aspergillosis can remain dormant over a long period. Although uncommon, it can occur in immunocompetent patients. FNA is a very useful tool in establishing the diagnosis 相似文献
103.
Potato chips industry wastewater was collected and analyzed for biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS) and total carbohydrates. Two Aspergillus species, A. foetidus and A. niger, were evaluated for their ability to grow and produce biomass and reduce the organic load of the wastewater. A. foetidus MTCC 508 and A. niger ITCC 2012 were able to reduce COD by about 60% and produce biomass 2.4 and 2.85 gl(-1), respectively. Co-inoculation of both Aspergillus strains resulted in increased fungal biomass production and higher COD reduction than in individual culture at different culture pH. pH 6 was optimum for biomass production and COD reduction. Amendment of the wastewater with different N and P sources, increased the biomass production and COD reduction substantially. Under standardized conditions of pH 6 and amendment of wastewater with 0.1% KH2PO4 and 0.1% (NH4)2 SO4, a mixed culture gave 90% reduction in COD within 60 h of incubation. 相似文献
104.
Natwar Singh Avinash Mishra Mukul Joshi Bhavanath Jha 《Plant Cell, Tissue and Organ Culture》2010,103(1):1-6
Pre-cultured cumin embryos were bombarded under 27 inches Hg vacuum, 25 mm distance from rupture disc to macrocarrier, 10 mm
macrocarrier flight distance using 1100 psi rupture disc and 9 cm microprojectile travel distance. An average of 110 embryos
was used per shot and 91% embryos showed transient GUS expression after 24 h. Shoot tips and roots of T0 plantlets exhibited GUS expression done after 3 months of bombardment. Transformation was confirmed with PCR amplification
of 0.96 and 1.3 kb band of hptII and gus genes respectively from T0 transgenics and southern blot analysis using PCR amplified DIG labeled hptII gene as probe. It is the first successful attempt of transformation of cumin plant through direct gene transfer using particle
gene gun and adequately exhibiting the possibility of stable transformation in cumin. 相似文献
105.
Divya Nedungadi Anupama Binoy Nanjan Pandurangan Bipin G. Nair Nandita Mishra 《Cell biology international》2021,45(1):164-176
Chalcones are biologically active class of compounds, known for their anticancer activities. Here we show for the first time that out of the six synthetic derivatives of chalcone tested, 2′-hydroxy-retrochalcone (HRC) was the most effective in inducing extensive cytoplasmic vacuolation mediated death called paraptosis in malignant breast and cervical cancer cells. The cell death by HRC is found to be nonapoptotic in nature due to the absence of DNA fragmentation, PARP cleavage, and phosphatidylserine externalization. It was also found to be nonautophagic as there was an increase in the levels of autophagic markers LC3I, LC3II and p62. Immunofluorescence with the endoplasmic reticulum (ER) marker protein calreticulin showed that the cytoplasmic vacuoles formed were derived from the ER. This ER dilation was due to ER stress as evidenced from the increase in polyubiquitinated proteins, Bip and CHOP. Docking studies revealed that HRC could bind to the Thr1 residue on the active site of the chymotrypsin-like subunit of the proteasome. The inhibition of proteasomal activity was further confirmed by the fluorescence based assay of the chymotrypsin-like subunit of the 26S proteasome. The cell death by HRC was also triggered by the collapse of mitochondrial membrane potential and depletion of ATP. Pretreatment with thiol antioxidants and cycloheximide were able to inhibit this programmed cell death. Thus our data suggest that HRC can effectively kill cancer cells via paraptosis, an alternative death pathway and can be a potential lead molecule for anticancer therapy. 相似文献
106.
Kulsoom Zahra Sandeep Patel Tulika Dey Uma Pandey Surendra Pratap Mishra 《Biochemistry and Biophysics Reports》2021
Cervical cancer is the second most common cause of cancer-related death among women worldwide, especially in developing countries. Oxidative stress has been associated with cervical cancer. Many studies demonstrated that the low level of antioxidants induces the production of free radicals that cause lipid peroxidation, DNA, and protein damage leading to mutations that favors malignant transformation. This is a case-control institutional study conducted to evaluate the level of oxidative stress in cervical cancer patients and the age-matched healthy controls. We measured level of TBARS expressed as MDA, activity of SOD and GSH level by the spectrophotometric method, and level of 8-OHdG was estimated using a competitive sandwich ELISA assay. Our results showed a significant increase in the level of lipid peroxidation in group IV when compared to the control, group II and group III (p < 0.001). The activity of SOD was also significantly higher in group IV when compared to the control group (p < 0.001), group II (p < 0.001), and group III (p < 0.001). The level of GSH was also significantly lower in group IV when compared to the control group (p < 0.01), group II (p < 0.01), and group III (p < 0.01). The level of 8-OHdG was significantly higher in group IV than in the other groups (p < 0.01). The results suggest that oxidative stress is involved in the pathogenesis of cervical cancer, which is demonstrated by an increased level of lipid peroxidation and higher levels of 8-OHdG and an altered antioxidant defense system. 相似文献
107.
Hydrogen sulphide is a common toxic contaminant in natural gas and oil. In this study, the strictly autotrophic bacterium Thiobacillus ferrooxidans , which oxidizes reduced sulphur compounds, was used to desulphur petroleum oil and gas. The reaction was carried out in a closed vessel containing substrate mixed with a bacterial suspension. The significance of the hydrogen sulphide oxidizing activity of T. ferrooxidans is discussed. 相似文献
108.
Bhupander Kumar V. K. Verma Meenu Mishra Richa Gaur Sanjay Kumar C. S. Sharma 《人类与生态风险评估》2014,20(6):1538-1549
Dichlorodiphenyltrichloroethane (DDT), hexachlorocyclohexane (HCH), and their isomers’ levels in residential soils were determined for the assessment of health risk in Korba, India. Observed concentrations of total HCH and total DDT in soils were more or less comparable with other parts of India and the world. ΣHCH and ΣDDT concentrations ranged between 0.9–20 μg kg?1 and 2–315 μg kg?1, respectively, which were lower than recommended soil quality guidelines indicating low ecotoxicological risk. Carcinogenic and non-carcinogenic impacts of HCH and DDT on human populations through soil ingestion were evaluated and presented. The incremental lifetime cancer risk (ILCR) for adults and children ranged between 7.8 × 10?10–1.6 × 10?7 and 4.1 × 10?9–8.2 × 10?7, respectively. Non-cancer health hazard quotient (HQ) ranged between 5.9 × 10?7–1.8 × 10?3 and 3.1 × 10?6–9.4 × 10?3, respectively, for adults and children. The estimated ILCR and HQ were within the safe acceptable limits of 10?6–10?4 and ≤1.0, respectively, indicating low risk to human populations from exposure to organochlorine pesticides (HCH and DDT) in the study area. 相似文献
109.
Manoj K. Mishra Pankaj Chaturvedi Ruchi Singh Gaurav Singh Lokendra K. Sharma Vibha Pandey Nishi Kumari Pratibha Misra 《PloS one》2013,8(4)
Background
Sterol glycosyltrnasferases (SGT) are enzymes that glycosylate sterols which play important role in plant adaptation to stress and are medicinally important in plants like Withania somnifera. The present study aims to find the role of WsSGTL1 which is a sterol glycosyltransferase from W. somnifera, in plant’s adaptation to abiotic stress.Methodology
The WsSGTL1 gene was transformed in Arabidopsis thaliana through Agrobacterium mediated transformation, using the binary vector pBI121, by floral dip method. The phenotypic and physiological parameters like germination, root length, shoot weight, relative electrolyte conductivity, MDA content, SOD levels, relative electrolyte leakage and chlorophyll measurements were compared between transgenic and wild type Arabidopsis plants under different abiotic stresses - salt, heat and cold. Biochemical analysis was done by HPLC-TLC and radiolabelled enzyme assay. The promoter of the WsSGTL1 gene was cloned by using Genome Walker kit (Clontech, USA) and the 3D structures were predicted by using Discovery Studio Ver. 2.5.Results
The WsSGTL1 transgenic plants were confirmed to be single copy by Southern and homozygous by segregation analysis. As compared to WT, the transgenic plants showed better germination, salt tolerance, heat and cold tolerance. The level of the transgene WsSGTL1 was elevated in heat, cold and salt stress along with other marker genes such as HSP70, HSP90, RD29, SOS3 and LEA4-5. Biochemical analysis showed the formation of sterol glycosides and increase in enzyme activity. When the promoter of WsSGTL1 gene was cloned from W. somnifera and sequenced, it contained stress responsive elements. Bioinformatics analysis of the 3D structure of the WsSGTL1 protein showed functional similarity with sterol glycosyltransferase AtSGT of A. thaliana.Conclusions
Transformation of WsSGTL1 gene in A. thaliana conferred abiotic stress tolerance. The promoter of the gene in W.somnifera was found to have stress responsive elements. The 3D structure showed functional similarity with sterol glycosyltransferases. 相似文献110.
A 6-m-deep lake has been sampled to measure the temporal and depth-wise distribution of heterotrophic bacteria and biological activity in the water. Surface, mid-depth and bottom waters were analysed at monthly intervals for a period of one year. The coefficient of heterotrophic activity, alkaline phosphatase activity and biological oxygen demand are used as an index of biological activity. The bacterial community was at maximum during spring, coinciding with high values of biological activity. Highest biological activity was observed in the bottom waters. Dissolved organic carbon showed a significant positive correlation with most of the biological activity parameters. This suggests that biological activity, as measured by the coefficient of heterotrophic activity, was more closely related to the concentration of substrates than to population density of heterotrophic bacteria. 相似文献