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51.
N-Methyl-4-nitroaniline (MNA) is used as an additive to lower the melting temperature of energetic materials in the synthesis of insensitive explosives. Although the biotransformation of MNA under anaerobic condition has been reported, its aerobic microbial degradation has not been documented yet. A soil microcosms study showed the efficient aerobic degradation of MNA by the inhabitant soil microorganisms. An aerobic bacterium, Pseudomonas sp. strain FK357, able to utilize MNA as the sole carbon, nitrogen, and energy source, was isolated from soil microcosms. HPLC and GC-MS analysis of the samples obtained from growth and resting cell studies showed the formation of 4-nitroaniline (4-NA), 4-aminophenol (4-AP), and 1, 2, 4-benzenetriol (BT) as major metabolic intermediates in the MNA degradation pathway. Enzymatic assay carried out on cell-free lysates of MNA grown cells confirmed N-demethylation reaction is the first step of MNA degradation with the formation of 4-NA and formaldehyde products. Flavin-dependent transformation of 4-NA to 4-AP in cell extracts demonstrated that the second step of MNA degradation is a monooxygenation. Furthermore, conversion of 4-AP to BT by MNA grown cells indicates the involvement of oxidative deamination (release of NH2 substituent) reaction in third step of MNA degradation. Subsequent degradation of BT occurs by the action of benzenetriol 1, 2-dioxygenase as reported for the degradation of 4-nitrophenol. This is the first report on aerobic degradation of MNA by a single bacterium along with elucidation of metabolic pathway. 相似文献
52.
Fahad A. Al-Abbasi 《Saudi Journal of Biological Sciences》2021,28(1):566-571
Regular exposure to stress causes alteration in biochemical parameter but till date no specific medicine prescribed for controlling it. Current study aimed to determine the effect of Diazepam on proinflammatory and cardiac markers in stress exposed rats. Male Wistar rats were divided into four groups with six animals in each group for 90 days study. Group-1 served as a Normal Control (NC), Groups-2, as a Disease Control (DC), Group-3 as a Diazepam Control (DMC) and Group-4 as a Disease + Diazepam Treatment (DT). DMC and DT animals exposed to regular stress by forced swimming exercise method for 90 days. DMC and DT received 5 mg/kg, p.o the daily dose of Diazepam. At the end of the protocol, animals were sacrificed. The level of serum proinflammatory marker interleukin-6 in DC increased significantly (p < 0.001) while restored significantly (p < 0.001) in DT. Level of interleukin-10 in DC decreased significantly (p < 0.001) while restored significantly (p < 0.001) in DT. Level of fibrinogen was also increased by stress, which was restored significantly (p < 0.05) by diazepam. Increased level of Creatine kinase-MB (CK-MB) by stress was restored significantly (p < 0.05) by diazepam. The level of cortisol was increased also significantly (p < 0.001) and restored to normal by diazepam. The level of C-reactive protein (CRP) and cholesterol was increased significantly (p < 0.01; p < 0.001) by stress while restored significantly (p < 0.01; p < 0.001) by diazepam. Findings from results suggest that diazepam ameliorates altered proinflammatory and cardiac markers in stress exposed rats. 相似文献
53.
Ajay Kumar Tiwari Kavita Kumari Neeraj Nath Tiwari Pradeep Kumar Akil Ahmad Khan 《Archives Of Phytopathology And Plant Protection》2013,46(17-20):931-935
During the survey of two successive years 2012–2013, in nearby places of Gorakhpur districts, Uttar Pradesh, India, Arundo donax plants were found to be exhibiting witches’ broom, excessive branching accompanied with little leaf symptoms with considerable disease incidence. Nested PCR carried out with universal primers pair R16F2n/R16R2 employing the PCR (P1/P7) product as a template DNA (1:20) resulted in expected size positive amplification ~1.2 kb in all symptom-bearing plants suggested the association of phytoplasma with witches’ broom disease of Narkat plants. BLASTn analysis of the 16S rRNA gene sequence showed the highest (99%) sequence identity with Candidatus phytoplasma asteris (16SrI group). In phylogenetic analysis, the sequence data showed close relationships with the members of 16SrI phytoplasma and clustered within a single clade of 16SrI group and closed to B subgroup representatives. This is a first report of 16Sr I-B group phytoplasma associated with witches’ broom accompanied with little leaf disease of Narkat in India. 相似文献
54.
Here, we have synthesized Ag2O3-ZnO nanocones (NCs) by a wet-chemical route using reducing agents at low temperature. The structural, optical and morphological properties of Ag2O3-ZnO NCs were investigated by several conventional techniques such as powder XRD, XPS, FESEM, XEDS, FTIR and UV/vis. spectroscopy. The analytical parameters of prepared NCs were also calculated for a selective detection of divalent cobalt [Co(II)] prior to its determination by inductively coupled plasma-optical emission spectrometry (ICP-OES). The selectivity of NCs toward various metal ions, including Cd(II), Co(II), Cr(III), Cu(II), Fe(III), Ni(II), and Zn(II) was studied. Results of the selectivity study demonstrated that Ag2O3-ZnO NC phase was the most selective towards Co(II) ion. The uptake capacity for Co(II) ion was experimentally calculated to be ∼76.69 mgg−1. Moreover, adsorption isotherm data provided that the adsorption process was mainly monolayer on homogeneous adsorbent surfaces of Ag2O3-ZnO NCs. Kinetic study revealed that the adsorption of Co(II) on Ag2O3-ZnO NCs phase followed the pseudo-second-order kinetic model. In addition, thermodynamic results provided that the adsorption mechanism of Co(II) ions on Ag2O3-ZnO NCs was a spontaneous process and thermodynamically favorable. Finally, the proposed method was validated by applying it to real environmental water samples with reasonable results. 相似文献
55.
A. Sai Ramesh Imran Khan Md. Farhan Padma Thiagarajan 《Cell biochemistry and biophysics》2013,67(3):1391-1396
CYP1A1 gene belongs to the cytochrome P450 family and is known better as smokers’ gene due to its hyperactivation as a consequence of long term smoking. The expression of CYP1A1 induces polycyclic aromatic hydrocarbon production in the lungs, which when over expressed, is known to cause smoking related diseases, such as cardiovascular pathologies, cancer, and diabetes. Single nucleotide polymorphisms (SNPs) are the simplest form of genetic variations that occur at a higher frequency, and are denoted as synonymous and non-synonymous SNPs on the basis of their effects on the amino acids. This study adopts a systematic in silico approach to predict the deleterious SNPs that are associated with disease conditions. It is inferred that four SNPs are highly deleterious, among which the SNP with rs17861094 is commonly predicted to be harmful by all tools. Hydrophobic (isoleucine) to hydrophilic (serine) amino acid variation was observed in the candidate gene. Hence, this investigation aims to characterize a candidate gene from 159 SNPs of CYP1A1. 相似文献
56.
Summary The ionic composition offour very productive and one unproductive fishpond has been investigated. The concentration of various ions is typical of carbonate waters except in two ponds for reasons of pollution. Calcium and bicarbonate are the major cation and anion while inspite of high productivity potassium is not very abundant. Because of the geographical position the area enjoys, the carbonate content seems to be important in productivity evaluation. For the same, its equivalent ratio to calcium and bicarbonate is very significant. 相似文献
57.
58.
M. Khan 《Hydrobiologia》1970,35(2):249-253
Summary The present communication deals with morphological features of a new fresh water species of the genus Acrochaetium
Naëg. (A. sarmaii sp. nov.). The occurrence of Compsopogon iyengarii is also recorded for the first time from a locality in North India. 相似文献
59.
60.