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221.
The strain BYT-1, capable of utilizing ODAP/DAP as a sole source of nitrogen and carbon was identified as Psuedomonas stutzeri by various microbial and biochemical tests. Transformation experiments showed that the ODAP utilizing property Is encoded by the plasmid. Restriction of plasmid DNA with Pstl, followed by cloning of fragments and screening of ODAP containing medium, led to the isolation of a clone with insert size of ?3.3 kb, which encoded ODAP metabolizing property. The growth and ODAP/DAP utilization by this clone (TB) was almost similar to that of the wild type strain.  相似文献   
222.
Genetic variation in fourteen isolates of Alternaria brassicae collected from different geographical regions of the world was determined by RAPD (random amplified polymorphic DNA) analysis. Twenty random primers were tried to amplify genomic DNA of A. brassicae. Based on the PCR (polymerase chain reaction) amplification of genomic DNA of A. brassicae with four oligonucleotide random primers, fingerprints were generated for each isolate and the amplifed products were compared. Using this technique, intra- and intercontinental genetic variation among isolates of A. brassicae could be distinguished.  相似文献   
223.
We have examined codon bias in 20 Brassica gene sequences collected from the literature. A comparison with the codon usage profile derived from 207 plant genes showed that Brassica genes distinctly differ from the plant genes with respect to Gly, Asp, Arg, lie, Try, Thr, Leu and Gin. Codon preferences for various amino acids did not differ among the three Brassica species, B. napus, B. oleracea and B. campestris considered in the present analysis. G ending codons for Thr, Ala, Pro and Ser are avoided by Brassica genes as in plant genes, in general. However, the avoidance of CG and TA doublets in Brassica genes is less than that observed in plant genes.  相似文献   
224.
Soft, nodular and hard types of calli were initiated on mature zygotic embryo explants of two tetraploid clones of Costus speciosus, of which, only the hard calli were amenable to morphogenetic responses. The two clones differed in their growth regulator requirements both for the initiation of calli and for shoot regeneration. De novo formation of both shoot bud meristems and somatic embryoids were observed. Latter were encased partially or fUlly by coleoptilar sheath. Embryoids could be isolated as discrete units. On maturity, a stock like appendage developed from the base and finally embryoids got detached from the subtending tissue. Both shoot-bud meristems and somatic embryoids developed into complete plantlets, the former upon sequential transfer of calli on Schenk and Hildebrandt’s (SH) basal medium containing lower levels of growth hormones, while the latter only on basal medium. These culture regenerants were subsequently transferred to the field. The morphogenetic behaviour of these two tetraploid clones reflects their marked genotypic difference inspite of their same ploidy status.  相似文献   
225.
Rapidly metabolizable compounds such as glucose or glycerol were not utilized byBacillus megaterium in the absence of manganese when grown in the supplemented nutrient broth medium. Under these conditions, growth ceased at low cell titre, 3-phosphoglyceric acid accumulated inside the cells and normal sporulation process was arrested. Addition of manganese to the medium caused disappearance of 3-phosphoglyceric acid, growth resumed and normal sporulation was observed. Synthesis of 3-phosphoglyceric acid occurred only in the mother cell compartments and it was transported for accumulation inside the forespores ofBacillus megaterium when grown in supplemented nutrient broth medium. Incubation of forespores in the presence of glucose or glycerol had no effect on 3-phosphoglyceric acid synthesis/accumulation, but it was completely utilized when forespores were incubated with manganese plus ionophore (X 537A). No other metal(s) could substitute for manganese suggesting that manganese plays crucial role in 3-phosphoglyceric acid metabolism  相似文献   
226.
Age-related changes in testosterone, progesterone and estradiol 17-beta were determined by radioimmunoassay (RIA) in the serum of 155 male buffalo calves of varying ages. The calves were classified into 17 age groups. The mean weight of calves increased from 33.6 +/- 9.6 kg at one week of age to 531 +/- 41.4 kg at 42 months. The testosterone levels were less than 100 pg/ml from birth until 15 months of age, followed by peak concentrations of 422 +/- 79 pg/ml at 24 to 30 months and 793 +/- 193 pg/ml at 42 to 48 months (corresponding to puberty and maturity, respectively). The progesterone levels were higher in newly born calves and mature bulls. Otherwise, the levels continued to be low throughout the period of growth and development. Estradiol 17-beta was significantly higher in postnatal calves up to two months of age. The testosterone revealed a positive correlation with weight and age while E2 17-beta showed a negative correlation with age. These results do not support a direct role of peripheral progesterone and estradiol 17-beta in the onset of puberty and sexual maturity of buffalo bulls.  相似文献   
227.
228.
This work aimed at the resolution of the multi-component electric potential changes induced by single-turnover flash illumination of Photosystem-I-enriched subchloroplast vesicles. If supplemented with ferredoxin and under carefully adjusted redox poising, these vesicles show a pronounced slow-rising and -decaying electric potential component, as monitored by endogenous and exogenous field-sensitive probes, carotenoids and oxonol VI, respectively. The fast and slow potential components can be easily discriminated without the need for computer-assisted deconvolution after selective presaturation of the slow component by preillumination or a transmembrane ΔpH, after selective suppression of the slow component by low valinomycin or uncoupler concentrations or in the absence of ferredoxin. The slow electric potential component, as compared to the fast one, is relatively sensitive to low concentrations of ionophores and uncouplers, detergent, ageing and lower temperatures (4–12°C), is associated with electrogenic proton displacements and is interpreted to respond to a field that is more located on the membrane-bulk interface. Temperature effects show transition temperatures around 20°C for both the rise and decay of the slow potential component. The results provide further evidence that the carotenoids and oxonol VI sense the same (slow) electric field, but may be differently located in the thylakoid membrane.  相似文献   
229.
The distribution of anthropometric measurements related to fatness levels is examined to determine if skewness alone accounts for the nonnormality of such measures. A mixture of two normal distributions or a single skewed distribution fit the data significantly better than a single normal in all cases. For maximum hip width, knee diameter, and weight, two skewed distributions give a better fit than one skewed distribution, rejecting the null hypothesis of a single distribution even when skewness is considered. There is evidence for three skewed component distributions for biceps skinfold. Abdomen circumference, upper arm circumference, triceps skinfold, and calf skinfold are best approximated by a one component log-normal distribution. Children and parents show slightly different patterns in skewness and kurtosis when considered separately, but differences between them do not account for the commingling found in the combined distributions.  相似文献   
230.
The intestinal uptake rate of oxalate (mumoles/h/g tissue wt.) in castrated male (CM) rats, CM rats administered estradiol, and female (F) rats was 1.8, 1.4 and 1.3 times higher than that of male rats, whereas castrated female (CF) rats and CF rats administered testosterone absorbed oxalate at a rate similar to F rats, thereby, suggesting that gonadectomy affected intestinal uptake of oxalate only in male rats The intestinal oxalate uptake rate in all the groups increased linearly with increasing oxalate concentration (0.1- 6.0 mM). Chemical composition of brush border membrane showed significant changes in the sialic acid, phospholipid and cholesterol content following castration, which may lead to ultrastructural changes in the membrane thereby, increasing the absorption of oxalate.  相似文献   
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