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排序方式: 共有103条查询结果,搜索用时 31 毫秒
71.
Chitra Pandey Vivek K. Bajpai Yogesh Kumar Negi Irfan A. Rather D.K. Maheshwari 《Saudi Journal of Biological Sciences》2018,25(6):1066-1071
Amaranth (Amaranthus hypochondriacus Linn.) is an important pseudocereal crop having important nutrients along with the indispensable amino-acids. The present study was aimed to study the effect of plant growth promoting bacilli on proximate constituents of amaranth grains, including three of the essential amino acids (methionine, lysine and, tryptophan). The combination of Bacillus pumilus and Bacillus subtilis showed a significant increase in different proximate constituents, including crude protein (22.13%), dry matter (32.25%), fat (30.77%), and carbohydrate (49.08%) in amaranth grains. Similarly, a significant increase in essential amino-acids (methionine 47.68%, lysine 59.41% and, tryptophan 38.05%) was recorded. This study suggests that the combination of Bacillus pumilus BS-27 and Bacillus subtilis BS-58 provides the natural, persistent and durable potential to enhance the nutritive value of the crop. Therefore, present study was designed to explore the enhancement of most desirable amino acid synthesis in amaranth due to application of plant growth promoting Bacillus spp. 相似文献
72.
Contribution of gentamicin 2'-N-acetyltransferase to the O acetylation of peptidoglycan in Providencia stuartii. 总被引:2,自引:2,他引:0
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A collection of Providencia stuartii mutants which either underexpress or overexpress aac(2')-Ia, the chromosomal gene coding for gentamicin 2'-N-acetyltransferase (EC 2.3.1.59), have been characterized phenotypically as possessing either lower or higher levels of peptidoglycan O acetylation, respectively, than the wild type. These mutants were subjected to both negative-staining and thin-section electron microscopy. P. stuartii PR100, with 42% O acetylation of peptidoglycan compared with 52% O acetylation in the wild type, appeared as irregular rods. In direct contrast, P. stuartii strains PR50.LM3 and PR51, with increased levels of peptidoglycan O acetylation (65 and 63%, respectively), appeared as coccobacilli and chain formers, respectively. Membrane blebbing was also observed with the chain-forming strain PR51. Thin sectioning of this mutant indicated that it was capable of proper constriction and separation. P. stuartii PM1, when grown to mid-exponential phase, did not have altered peptidoglycan O-acetylation levels, and cellular morphology remained similar to that of wild-type strains. However, continued growth into stationary phase resulted in a 15% increase in peptidoglycan O acetylation concomitant with a change of some cells from a rod-shaped to a coccobacillus-shaped morphology. The fact that these apparent morphological changes were directly related to levels of O acetylation support the view that this modification plays a role in the maintenance of peptidoglycan structure, presumably through the control of autolytic activity. 相似文献
73.
74.
Aehtesham Hussain Muzafar A. Rather Mohd S. Dar Mushtaq A. Aga Nisar Ahmad Aabid Manzoor Arem Qayum Aiyatullah Shah Saleem Mushtaq Zahoor Ahmad Qazi P. Hassan 《Bioorganic & medicinal chemistry letters》2017,27(11):2579-2582
A new eudesmane sesquiterpenoid (1), and a new homologue of virginiae butanolide E (2) along with butyl isobutyl phthalate (3) were isolated from, actinomycete-Lentzea violacea strain AS08 isolated from north western Himalayas by stressing on modified one strain-many compounds (OSMAC) method. The structures of the new compounds were elucidated by extensive spectroscopic analyses including 1D, 2D NMR along with HR-ESI-MS and FT-IR data. Herein, a distinctive method was added for inspecting secretory profile of the strain by quantification of extract value of cell free supernatant in different types of culture media fallowed by HPLC profiling of respective extracts, which revealed a highly altered metabolic profile of the strain and formed the base for the selection of media. The compounds 1 and 2 showed moderate activity against Gram negative (MIC ~32–64 µg ml?1) in comparison to Gram positive bacterial pathogens. Compound 1 exhibited significant activity in human cancerous cell lines (IC50 ~19.2 µM). 相似文献
75.
Sadaf Rafiq Z.A. Rather Reyaz Ahmad Bhat I.T. Nazki Mohammad S. AL-Harbi Neelofar Banday Iqra Farooq Bassem N. Samra M.H. Khan Atef F. Ahmed Najmah Andrabi 《Saudi Journal of Biological Sciences》2021,28(12):7581
Micropropagation protocol of Oriental Hybrid Lilium cv. Ravenna was developed using bulb scale segments (Basal and Tip) as explants. Surface sterilization of healthy bulb scales with carbendazim 200 ppm for 30 min, then 0.1 percent mercuric chloride for 10 min, then 70% ethyl alcohol for 30 s was superior to all other treatments in recording highest culture asepsis (77.08%) and higher explant survival (86.12%). Explant survival was higher in basal segments (88.54%) compared to tip segments (85.52%). Highest culture establishment was recorded in basal scale segments (68.26%) followed by tip scale segments (55.21%). MS medium augmented with 0.50 mgl−1 Naphthalene acetic acid and 2.0 mgl−1. 6-Benzylamino Purine recorded maximum culture establishment (76.17%), highest bulblet number/explant (5.52) with maximum length of shoots (2.20 cm) and number of leaves (3.39). This treatment combination of growth regulators resulted in highest shoot proliferation (83.33%) along with maximum shoot number (2.41explant−1), shoot length (2.35 cm) and leaf number (5.44) of micro shoots during proliferation stage. Rooting of explants was superior with Indole-3-butyric acid compared to Naphthalene acetic acid. Highest rooting of 92.71% along with maximum number of primary roots shoot−1 (12.06), maximum primary root length (3.17 cm) was documented in Murashige and Skoog medium added with Indole-3-butyric acid 1.50 mgl−1 with best ex vitro survival rate (98.96%) of rooted plantlets during primary hardening in perlite + vermiculite (1:1) mixture. 相似文献
76.
Eijaz Ahmed Bhat Nasreena Sajjad Irfan A. Rather Jamal S.M. Sabir Yan-Yan Hor 《Saudi Journal of Biological Sciences》2021,28(12):7511-7516
BackgroundTumor necrosis factor interacting protein (TRAIP/TRIP) is an important cell-signaling molecule that prevents the TNF-induced-nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation via direct interaction with TRAF 2 protein. TRAIP is a crucial downstream signaling molecule, implicated in several signaling pathways. Due to these multifunctional effects, TRAIP is more related to cellular mitosis, chromosome segregation, and DNA damage response. Tumor necrosis factor interacting protein is a downstream signaling molecule that contains a RING domain with E3 ubiquitin ligase activity at the N terminal side followed by coiled-coil and C terminal leucine zipper domain. Human TRAIP is constituted of 469 amino acids with 76% sequence similarity with the mouse TRAIP protein. Although, the main inhibitory function of TRAIP has been known for decades, however, in vitro interaction of TRAIPCC domain with RAP80 Zinc finger motif has not been reported yet. Besides, RAP80, the binding partner of TRAIPCC protein has been implicated in DNA damage response.ResultsOur in vitro study shows that the TRAIP CC (64–166) associates with the RAP80 zinc finger of corresponding amino acid 490–584. However, TRAIP CCLZ (66–260) and TRAIP RINGCC (1 = 157) failed to interact with the RAP80 zinc finger of corresponding amino acid 490–584. The current study reinforces TRAIP CC (64–166) and RAP80 zinc finger of corresponding amino acid 490–584 associates to form a complex. Moreover, SDS PAGE arbitrated the homogeneity of RAP80 Zinc finger and TRAIP CC of corresponding amino acid 490–584 and 64–166, respectively.ConclusionIn vitro, a specific interaction was observed between the TRAIP CC (64–166) and the RAP80 zinc finger of the corresponding amino acid 490–584 and a specific binding area of the RAP80 zinc finger motif were investigated. The TRAIPCC region is required for the complex to bind to the RAP80-Zn finger motif. This strategy may be necessary for the RAP80 zinc finger activity to the TRAIP CC protein. 相似文献
77.
Previous work has shown that lacZ fusions to the cysK, astD, tnaB, and gabT genes in Escherichia coli are activated by self-produced extracellular signals. Using a combination of ethyl acetate extraction, reversed-phase C(18) chromatography, and thin-layer chromatography, we have purified an extracellular activating signal from E. coli supernatants. Mass spectrometry revealed a molecule with an m/z peak of 117, consistent with indole. Nuclear magnetic resonance analysis of the purified E. coli factor and synthetic indole revealed identical profiles. Using synthetic indole, a dose-dependent activation was observed with lacZ fusions to the gabT, astD, and tnaB genes. However, cysK::lacZ and several control fusions were not significantly activated by indole. Conditioned medium prepared from a tnaA (tryptophanase) mutant, deficient in indole production, supported 26 to 41% lower activation of the gabT and astD fusions. The residual level of activation may be due to a second activating signal. Activation of the tnaB::lacZ fusion was reduced by greater than 70% in conditioned medium from a tnaA mutant. 相似文献
78.
79.
Liv J. Rather Bettina Knapp Wolfgang Haehnel Georg Fuchs 《The Journal of biological chemistry》2010,285(27):20615-20624
In the aerobic metabolism of aromatic substrates, oxygenases use molecular oxygen to hydroxylate and finally cleave the aromatic ring. In the case of the common intermediate benzoate, the ring cleavage substrates are either catechol (in bacteria) or 3,4-dihydroxybenzoate (protocatechuate, mainly in fungi). We have shown before that many bacteria, e.g. Azoarcus evansii, the organism studied here, use a completely different mechanism. This elaborate pathway requires formation of benzoyl-CoA, followed by an oxygenase reaction and a nonoxygenolytic ring cleavage. Benzoyl-CoA transformation is catalyzed by the iron-containing benzoyl-CoA oxygenase (BoxB) in conjunction with an FAD and iron-sulfur centers containing reductase (BoxA), which donates electrons from NADPH. Here we show that benzoyl-CoA oxygenase actually does not form the 2,3-dihydrodiol of benzoyl-CoA, as formerly postulated, but the 2,3-epoxide. An enoyl-CoA hydratase (BoxC) uses two molecules of water to first hydrolytically open the ring of 2,3-epoxybenzoyl-CoA, which may proceed via its tautomeric seven-membered oxepin ring form. Then ring C2 is hydrolyzed off as formic acid, yielding 3,4-dehydroadipyl-CoA semialdehyde. The semialdehyde is oxidized by a NADP+-dependent aldehyde dehydrogenase (BoxD) to 3,4-dehydroadipyl-CoA. Final products of the pathway are formic acid, acetyl-CoA, and succinyl-CoA. This overlooked pathway occurs in 4–5% of all bacteria whose genomes have been sequenced and represents an elegant strategy to cope with the high resonance energy of aromatic substrates by forming a nonaromatic epoxide. 相似文献
80.
Functional characterization of Escherichia coli GlpG and additional rhomboid proteins using an aarA mutant of Providencia stuartii
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The Providencia stuartii AarA protein is a member of the rhomboid family of intramembrane serine proteases and required for the production of an extracellular signaling molecule that regulates cellular functions including peptidoglycan acetylation, methionine transport, and cysteine biosynthesis. Additional aarA-dependent phenotypes include (i) loss of an extracellular yellow pigment, (ii) inability to grow on MacConkey agar, and (iii) abnormal cell division. Since these phenotypes are easily assayed, the P. stuartii aarA mutant serves as a useful host system to investigate rhomboid function. The Escherichia coli GlpG protein was shown to be functionally similar to AarA and rescued the above aarA-dependent phenotypes in P. stuartii. GlpG proteins containing single alanine substitutions at the highly conserved catalytic triad of asparagine (N154A), serine (S201A), or histidine (H254A) residues were nonfunctional. The P. stuartii aarA mutant was also used as a biosensor to demonstrate that proteins from a variety of diverse sources exhibited rhomboid activity. In an effort to further investigate the role of a rhomboid protein in cell physiology, a glpG mutant of E. coli was constructed. In phenotype microarray experiments, the glpG mutant exhibited a slight increase in resistance to the beta-lactam antibiotic cefotaxime. 相似文献