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1.
Eight of 104 fast-growing strains of Rhizobium sp. ( Sesbania ) tested possessed a hydrogen recycling system. Depression of uptake hydrogenase occurred in poor as well as in rich carbon media. A statistically significant increase (> 22%) in total plant nitrogen content and dry matter yield was observed by the inoculation of hup + strains over hup - strains. 相似文献
2.
R. Nagpal S. N. Raina Y. S. Sodhi A. Mukhopadhyay N. Arumugam A. K. Pradhan D. Pental 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(5):566-571
For the transfer of genes from B. tournefortii (TT) to the allotetraploid oilseed brassicas, B. juncea AABB, B. carinata BBCC and B. napus AACC, B. tournefortii was first crossed with the three basic diploid species, B. campestris (AA), B. nigra (BE) and B. oleracea (CC), to produce the allodiploids TA, TB and TC. These were tetraploidized by colchicine treatment to produce the allotetraploids TTAA, TTBB and TTCC, which were further crossed with B. juncea and B. napus to produce three-genome hybrids with substitution-type genomic configurations: TACC, TBAA and TCAA. These hybrids along with another hybrid TCBB produced earlier, the three allodiploids, their allotetraploids and the four diploid parent species were studied for their male meiotic behaviour. The diploid parent and the allotetraploids (TTAA, TTBB and TTCC) showed regular meiosis although the pollen viability was generally low in the allotetraploids. In the allodiploids (TA, TB and TC) only some end-to-end associations were observed without any clearly discernible chiasmata or exchange points. Chromosomes involved in end-to-end associations were randomly distributed at the metaphase/anaphase-I stages. In contrast, the three-genome hybrids (TACC, TBAA, TCAA and TCBB) showed normal bivalents whose number exceeded the expected bivalent values. Bivalents arising out of homoeologous pairing were indistinguishable from normal pairs by their disjunction pattern but could be distinguished on the basis of the heteromorphy of the homoeologous chromosomes. The three-genome hybrids could be backcrossed to allotetraploid oilseed brassicas as they had some fertility. In contrast, the allodiploids could neither be selfed nor back-crossed. On the basis of their meiotic stability, in terms of more pronounced homoeologous pairing and fertility for backcrossing, the three-genome configurations provide the best possible situation for the introgression of alien genes from the secondary gene pool to the allotetraploid oilseed crops B. juncea, B. napus and B. carinata. 相似文献
3.
The effect of carbon dioxide concentration on the bacterial leaching of a pyrite-arsenopyrite ore concentrate was studied in continuous-flow reactors. Steady-state operation with two feed slurry densities, 6 wt% and 16 wt% solids, were tested for the effect of carbon dioxide concentration. Bacterial growth rates were estimated via the measurement of carbon dioxide consumption rates. Aqueous-phase carbon dioxide concentrations in excess of 10 mg/L were found to be inhibitory to bacterial growth. (c) 1993 John Wiley & Sons, Inc. 相似文献
4.
The use of s-2-cyanoethyl phosphorothioate in the preparation of oligo 5''-deoxy-5''-thiothymidylates. 总被引:2,自引:2,他引:0 下载免费PDF全文
An improvement of our strategy for the stepwise synthesis of oligo 5'-deoxy-5'-thiodeoxyribonucleotides [Chladek and Nagyvary (1972) J. Amer. Chem. Soc. 94, 2079] involves the use of 5'-O-tosylthymidine 3'-S-2-cyanoethyl phosphorothioate. The displacement of the tosylate by thymidine 3'-phosphorothioate and subsequent alkaline deblocking afforded the dinucleotide (Tps)2. The process of displacement and deblocking was repeated three more times at an average yield of 30 percent per step. The corresponding bifunctional derivative of deoxyadenosine was found much less reactive and practically unsuitable for repeated chain elongation. The ORD and CD spectra of the analogs are similar to those of the natural oligonucleotides. 相似文献
5.
Avinash M. Veerappa Prakash Padakannaya Nallur B. Ramachandra 《Functional & integrative genomics》2013,13(3):285-293
A 3.5-Mb region of the X chromosome underwent duplication and transposition to the Y chromosome ~5–6 Mya. This X-transposed-region (XTR) originated at Xq21.3 and was inserted at Yp11.2. The two locations have 98.78 % homology and a high concentration of tandem repeats. In whole-genome scans of ten large families with dyslexic members, we identified transposed blocks comprising >102 kb of the Yp11.2 region in its homologous region at Xq21.3 in three females from three different families. Although recombination is known to be limited only to the pseudoautosomal regions (PARs) of the X and Y chromosomes, we report allelic unequal recombination between the XTR region Yp11.2 and Xq21.3, indicating the presence of a new PAR, which we named PAR3. This PAR3 region was also found in 2 % of the general population. An additional layer of justification could be provided from six other dyslexic cases which harbored duplications and deletions in the same Xq21.3 and Yp11.2 regions through allelic unequal recombination. 相似文献
6.
J P Nagpal R K Wali R Singh S Farooqui S Majumdar A Mahmood 《Biochemical medicine》1985,34(2):207-213
The effect of isatin (indole-2,3-dione) on D-glucose uptake has been studied in rat intestine. Isatin at 6 mM concentration significantly inhibited both the sugar uptake and transmural (mucosal to serosal side) transport in the intestine. The suppression of glucose uptake by isatin was irreversible. Similar to the action of various SH-group-reacting agents, isatin inhibited the sugar uptake, presumably by binding to membrane sulfhydryl groups through a covalent linkage. Isatin-induced reduction in glucose uptake was unaffected by pH (between 5.5 and 8.4) and by DTT addition to incubation medium. Inhibition of sugar uptake by isatin and harmaline was additive in nature; this suggested that these compounds interact at different sites on the microvillus membrane surface. 相似文献
7.
Noe Fernandez‐Pozo Fabian B. Haas Rabea Meyberg Kristian K. Ullrich Manuel Hiss Pierre‐Franois Perroud Sebastian Hanke Viktor Kratz Adrian F. Powell Eleanor F. Vesty Christopher G. Daum Matthew Zane Anna Lipzen Avinash Sreedasyam Jane Grimwood Juliet C. Coates Kerrie Barry Jeremy Schmutz Lukas A. Mueller Stefan A. Rensing 《The Plant journal : for cell and molecular biology》2020,102(1):165-177
Physcomitrella patens is a bryophyte model plant that is often used to study plant evolution and development. Its resources are of great importance for comparative genomics and evo‐devo approaches. However, expression data from Physcomitrella patens were so far generated using different gene annotation versions and three different platforms: CombiMatrix and NimbleGen expression microarrays and RNA sequencing. The currently available P. patens expression data are distributed across three tools with different visualization methods to access the data. Here, we introduce an interactive expression atlas, Physcomitrella Expression Atlas Tool (PEATmoss), that unifies publicly available expression data for P. patens and provides multiple visualization methods to query the data in a single web‐based tool. Moreover, PEATmoss includes 35 expression experiments not previously available in any other expression atlas. To facilitate gene expression queries across different gene annotation versions, and to access P. patens annotations and related resources, a lookup database and web tool linked to PEATmoss was implemented. PEATmoss can be accessed at https://peatmoss.online.uni-marburg.de 相似文献
8.
Xiangming Li Yujian Zhang Li Jing Zongming Fu Ou Ma Jishna Ganguly Nilesh Vaidya Richard Sisson Jennifer Naginskaya Avinash Chinthala Minggang Cui Ryan Yamagata Mark Wilson Matthew Sanders Zihao Wang Paola Lo Surdo Marcin Bugno 《Biotechnology progress》2020,36(2):e2914
Mammalian cell line generation typically includes stable pool generation, single cell cloning and several rounds of clone selection based on cell growth, productivity and product quality criteria. Individual clone expansion and phenotype-based ranking is performed initially for hundreds or thousands of mini-scale cultures, representing the major operational challenge during cell line development. Automated cell culture and analytics systems have been developed to enable high complexity clone selection workflows; while ensuring traceability, safety, and quality of cell lines intended for biopharmaceutical applications. Here we show that comprehensive and quantitative assessment of cell growth, productivity, and product quality attributes are feasible at the 200–1,200 cell colony stage, within 14 days of the single cell cloning in static 96-well plate culture. The early cell line characterization performed prior to the clone expansion in suspension culture can be used for a single-step, direct selection of high quality clones. Such clones were comparable, both in terms of productivity and critical quality attributes (CQAs), to the top-ranked clones identified using an established iterative clone screening approach. Using a complex, multi-subunit antigen as a model protein, we observed stable CQA profiles independently of the cell culture format during the clonal expansion as well as in the batch and fed-batch processes. In conclusion, we propose an accelerated clone selection approach that can be readily incorporated into various cell line development workstreams, leading to significant reduction of the project timelines and resource requirements. 相似文献
9.
SoRi Jang Zhao Xuan Ross C. Lagoy Louise M. Jawerth Ian J. Gonzalez Milind Singh Shavanie Prashad Hee Soo Kim Avinash Patel Dirk R. Albrecht Anthony A. Hyman Daniel A. Colón-Ramos 《Biophysical journal》2021,120(7):1170-1186
Although much is known about the biochemical regulation of glycolytic enzymes, less is understood about how they are organized inside cells. We systematically examine the dynamic subcellular localization of glycolytic protein phosphofructokinase-1/PFK-1.1 in Caenorhabditis elegans. We determine that endogenous PFK-1.1 localizes to subcellular compartments in vivo. In neurons, PFK-1.1 forms phase-separated condensates near synapses in response to energy stress from transient hypoxia. Restoring animals to normoxic conditions results in cytosolic dispersion of PFK-1.1. PFK-1.1 condensates exhibit liquid-like properties, including spheroid shapes due to surface tension, fluidity due to deformations, and fast internal molecular rearrangements. Heterologous self-association domain cryptochrome 2 promotes formation of PFK-1.1 condensates and recruitment of aldolase/ALDO-1. PFK-1.1 condensates do not correspond to stress granules and might represent novel metabolic subcompartments. Our studies indicate that glycolytic protein PFK-1.1 can dynamically form condensates in vivo. 相似文献
10.
Christian Schimper Rupert Keckeis Eduard Burtscher Avinash P. Manian 《Biocatalysis and Biotransformation》2013,31(5-6):383-389
Cellulosic fabric samples of cotton, viscose, lyocell and modal were pretreated with steam and dry heat in the range of 100–190°C. The samples were then treated with a Trichoderma reesei cellulase preparation (total culture filtrate – TC), with mechanical agitation, at a high enzyme dosage of 75% by weight of fabric, for 8 hours. Generally, viscose proved to be easily degradable, followed by cotton and modal. The degree of hydrolysis was the least for Lyocell. Dry heat pretreatments exerted a lower influence on degradation rate than steam pretreatments which showed a distinct maximum at a steam temperature of 130°C. The hydrolysis rate varied strongly depending on treatment conditions and fibre type. Water retention values in treated substrates were changed by up to 20% of initial values. 相似文献