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271.
The role of humoral antibodies and the effect of BCG vaccination were studied in the experimental candidiasis in mice. The antibody suppressed, B-cell deficient animals were prepared by repeated administration of rabbit anti-mouse--antiserum to the new born mice from birth onwards. Such immunodeficient animals along with controls were infected intravenously with Candida albicans, to study the course of candidal infection. It was observed that B-cell-deficient animals were found to be more susceptible to candidal infection than the controls, as indicated by their steady loss of body weight, longer mean time to death and higher viable counts of candidal cells in different organs. The anti-candidal antibodies were absent in all B-cell-deficient animals but present in the controls. These results suggest that antibodies make a contribution in protection against candidal infection in mice. The BCG vaccinated animals were prepared by repeated intravenous administration of BCG to mice and these vaccinated animals along with unvaccinated controls were challenged intravenously with C. albicans, to study the course of candidal infection. It was observed that BCG vaccination prolonged meantime to death and reduced the number of candidal cells in their kidneys. 相似文献
272.
Summary Immobilization of -chymotrypsin was done by cross-linking the enzyme with glutaraldehyde. Studies were done in a batch reactor to find out the effects of the concentrations of -chymotrypsin and glutaraldehyde on the rate of particle formation, the final yield of the crosslinked particles, and the residual activity of the cross-linked enzyme. Both intra- and inter-molecular cross-linking play important role at different time course of the reaction. At the begining of the cross-linking reaction, the large drop in the activity is because of the intra-molecular cross-linking and later on the large increase in the particle formation is because of the inter-molecular cross-linking. 相似文献
273.
The bacterium Arthrobacter ilicis isolated from the marine sponge Spirastrella sp. produces extracellular serine type acetylcholinesterase. The maximum enzyme activity was found at 45 °C and pH 8·0. The activation and deactivation energies, calculated from an Arrhenius plot, were 13·68 and 36·96 kcal mol−1 , respectively. The enzyme was not affected by the addition of the major cations of sea water, such as Ca2+ and Mg2+ at 25 mmol l−1 , and was strongly inhibited by EDTA and different organophosphorus and carbamate compounds at 5 mmol l−1. 相似文献
274.
Random chloroplast segregation and mitochondrial genome recombination in somatic hybrid plants of Diplotaxis catholica+Brassica juncea 总被引:4,自引:0,他引:4
T. Mohapatra P. B. Kirti V. Dinesh Kumar S. Prakash V. L. Chopra 《Plant cell reports》1998,17(10):814-818
Detailed molecular analysis of the somatic hybrid plants of Diplotaxis catholica+B. juncea indicated random chloroplast segregation. One of the five hybrid plants analyzed derived its chloroplasts from D. catholica and two hybrids had chloroplasts of B. juncea origin. Two hybrid plants maintained mixed population of chloroplasts. The mitochondrial (mt) genomes of the fusion partners
had undergone recombinations. Occurrence of fragments specific to both the parents in HindIII digestion followed by atp 9 probing, as in hybrid DJ5, provided evidence for intergenomic mitochondrial recombination between D. catholica and B. juncea. Similar mt genome organization in two hybrids (DJ3 and DJ6) suggested that intergenomic recombination may be preferred at
specific sites. Hybrid DJ1 had about 70% similarity to D. catholica in mt genome organization. mt genomes of hybrids DJ2, 3, 5, and 6 differed from B. juncea by 14.3–28%. The significance of these novel mt genome organizations in developing novel male sterility systems is discussed.
Received: 4 April 1997 / Revision received: 19 December 1997 / Accepted: 28 March 1998 相似文献
275.
In India, molecular mapping and tagging of agronomically important genes using RFLP and RAPD markers have been carried out in three different crops: rice, mustard and chickpea. In rice, tagging of genes for resistance to gall midge and blast has been accomplished. Molecular mapping of cooking quality traits in rice is in progress. For fingerpringting rice cultivars, suitable probe enzyme combinations have been identified. In mustard, a partial RFLP linkage map has been constructed and one of the yellow seed-coat colour loci has been mapped. Significant associations of RFLP markers with quantitative traits have also been established. Potential use of RAPD markers to identify heterotic groups among mustard accessions has been demonstrated. In chickpea, the occurrence of considerable interspecific DNA polymorphism as revealed by RAPD analysis has facilitated construction of a partial linkage map. 相似文献
276.
Characterization of a gene family encoding abscisic acid- and environmental stress-inducible proteins of alfalfa. 总被引:10,自引:0,他引:10
M Luo J H Liu S Mohapatra R D Hill S S Mohapatra 《The Journal of biological chemistry》1992,267(22):15367-15374
The phytohormone abscisic acid (ABA) has been proposed as a common mediator controlling adaptive plant responses to a variety of environmental stresses, including water deficit, salinity, wounding, and low temperature. We have recently isolated three cDNAs, pUM90-1, pUM90-2, and pUM91-4, from a cDNA library of ABA-induced mRNAs of alfalfa. These cDNA clones exhibit a very high degree of sequence homology with one another and sequence similarities with certain regions of several stress- and ABA-inducible genes. The polypeptides encoded by these cDNAs are very rich in glycine (35-40%), histidine (7-15%), asparagine (8-14%), and tyrosine (5-10%) and have no tryptophan and proline. All of the encoded polypeptides contain characteristic tandem repeats comprising glycine residues intercepted with histidine and/or tyrosine. The RNAs corresponding to a representative cDNA, pUM90-1, were induced after treatment of seedlings with low temperature, drought, salt, and wounding stress, but not by heat; the induction was maximal under low temperature treatment. ABA and ABA analog rapidly induced the expression of these genes, whereas gibberellic acid treatment exhibited no induction whatsoever. These genes appear to be specifically induced in the shoot tissues. Analysis of ABA induction of genes corresponding to pUM90-1 in alfalfa seedlings of different age groups demonstrated that these genes were inducible in seedlings/plants of all age groups examined. Taken together these results suggest that these cDNA clones encode a group of proteins that are inducible by ABA and multiple environmental stresses and correspond to a new family of genes of plants, designated as ABA- and environmental stress-inducible genes. 相似文献
277.
278.
Summary Intergeneric somatic hybrids Diplotaxis catholica (2n=18) + Brassica juncea (2n=36) were produced by fusing mesophyll protoplasts of the former and hypocotyl protoplasts of the latter using polyethylene glycol. Out of 52 somatic embryos, 24 produced plants of intermediate morphology. Cytological analysis of 16 plants indicated that 15 were symmetric hybrids carrying 54 chromosomes, the sum of the parental chromosome numbers. One hybrid was asymmetric with 45 chromosomes. Nuclear hybridity of five putative hybrids was confirmed by the Southern hybridization pattern of full length 18s-25s wheat nuclear rDNA probe which revealed the presence of Hind III fragments characteristic of both the parental species. The hybridization pattern of mitochondria specific gene probe cox I indicated that three of the hybrids carried B. juncea mitochondria and one carried mitochondria of D. catholica. Presence of novel 3.5 kb Hind III and 4.8 kb Bgl II fragments suggested the occurrence of mtDNA recombination in one of the hybrids. The hybrids were pollen sterile. However, seeds were obtained from most of the hybrids by back crossing with B. juncea. 相似文献
279.
280.
Swarup K. Parida Sanjay Kalia Awadhesh Pandit Preetam Nayak Ram Kushal Singh Kishor Gaikwad Prem Shankar Srivastava Nagendra K. Singh Trilochan Mohapatra 《Plant cell reports》2016,35(8):1629-1653