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Jerome F. Fredrick 《Phytochemistry》1977,16(1):55-57
Gel electrophoresis of the glucosyltransferases of the blue-green alga, Oscillatoria princeps, followed by immunodiffusion against anti-phosphorylase rabbit serum, showed cross-reactions of the two phosphorylase isozymes and the two synthetase isozymes of the alga. Weak cross-reactions were also obtained with the branching isozymes. Apparent extensive similarities in the structure of the phosphorylases and the synthetases were indicated. However, only partial structural similarities between the two groups of α-1,4-glucosidic bond formers and the branching isozymes exist as indicated by the weak immunological reactions obtained and the formation of “spurs” on the immunoprecipitin lines. If the synthesis of α-1,4-glucosidic linkages and the formation of α-1,6 cross linkages were at one time due to the bifunctional action of a single catalytic protein, then the separation of these two enzymatic activities took place prior to the derivation of the synthetases from the phosphorylases. 相似文献
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The Sable antelope (Hippotragus niger roosevelti, Heller, 1910) is nationally endemic to Shimba Hills National Reserve (SHNR) in Kenya. In the past few decades, its population has declined considerably. Despite the alarming decline and resultant localised distribution, a little information exists on the species population status and foraging ecology. Different ecological research techniques were used to collect relevant data and information on the species population structure and feeding habits. The results showed that Sable population comprised of sex and age structures that are skewed towards females and adult, respectively, whereas young and subadult populations were not significantly different. Seasonal change did not have significant influence on the diversity of food plants selected by Sable. Although crude protein and phosphorous levels in Sable faecal samples differed significantly between the seasons, they were within the recommended minimum maintenance requirements for wild herbivores. The study concludes that Sable has good survival rate and potential to breed but lacks stability in the population. Additionally, Sable forage quality and availability may not be limiting its population growth. There is need to establish management strategies for improving reproduction in Sable and understand the level of competition of the species with other mega herbivores in SHNR. 相似文献
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