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631.
Localisation of a prophenoloxidase in the cytoplasm of plasmatocytes was histochemically demonstrable in Corcyra cephalonica, by incubating the blood with different phenolic substrates. The activation of this latent enzyme was found to be controlled by a protein factor present in the cuticle. The haemolymph prophenoloxidase could be activated in vitro by prior incubation of the blood sample at 0°C. The treatment with NaCl, EDTA, or detergents did not cause any activation. The exposure of blood samples to gamma-rays, repeated freezing and thawing, or addition of the cuticular activator, brought about rapid disruption of the haemocytes causing a release of phenoloxidase and acceleration of melanization of the blood. The administration of α-ecdysone to the last instar larvae induced premature pupation and accentuated the activation of phenoloxidase without altering the level of enzyme activity. The possible regulatory mechanisms of tanning during the development of Corcyra have been discussed. 相似文献
632.
633.
Renjithkumar Chelapurath Radhakrishnan Roshni Kuttanelloor Rajeev Raghavan Ranjeet Kutty 《Zeitschrift fur angewandte Ichthyologie》2020,36(5):699-704
We provide the first record of the Mayan Cichlid, Mayaheros urophthalmus from South Asia, based on specimens collected from the River Chalakudy in Kerala, India. Genetic analysis of the Indian sample showed close affinity with those from Philippines suggesting their potential South East Asian origin, and introduction through the unmanaged aquarium trade. Ecological plasticity, opportunistic predatory behaviour and eurytopic nature of M. urophthalmus could facilitate colonization in the new environment, unless urgent management strategies are developed and implemented. 相似文献
634.
Chinthapalli Bhaskarrao Raghavan Chitra Bläsing O. Westhoff P. Raghavendra A.S. 《Photosynthetica》2000,38(3):415-419
Photosynthetica - Phosphoenolpyruvate carboxylase (PEPC) was purified from leaves of four species of Alternanthera differing in their photosynthetic carbon metabolism: Alternanthera sessilis (C3),... 相似文献
635.
Usha Natraj K. S. N. Iyer Vijaya Raghavan Smita Mahale Jacintha Pereira 《Journal of biosciences》1990,15(4):341-350
The antigenecity of tryptic fragments of reduced and carboxymethylated chicken riboflavin carrier protein were studied. The
tryptic sites of the native riboflavin carrier protein bound to riboflavin were inaccessible. The molecular weight and the
elution profile on high performance liquid chromatography (TSK 545 DEAE) were unaltered at an enzyme to substrate ratio of
1:31. However, carboxymethylated riboflavin carrier protein could be cleaved into 3 or 4 fragments at an enzyme to substrate
ratio of 1:250 or 1:125. Chromatographic separation of the tryptic fragments on high pressure liquid chromatography (TSK 545
DEAE) revealed the presence of two fragments with different elution profiles but similar molecular weight 26 ±2 kDa. Only
one fragment (associated with peak 2) had the ability to displace chicken riboflavin carrier protein in an homologous chicken
riboflavin carrier protein radioimmunoassay. Thus, carboxymethylated ribotlavin carrier protein which does not compete with
chicken riboflavin carrier protein in the radioimmunoassay, on mild trypsinization generates a fragment which interacts with
chicken riboflavin carrier protein in radioimmunoassay. 相似文献
636.
J Alroy A Bachrach J G Thalhammer N Panjwani R Richard R DeGasperi C D Warren D M Albert S S Raghavan 《Virchows Archiv. B, Cell pathology including molecular pathology》1991,60(3):173-180
The clinical, neurophysiological, morphological and biochemical manifestation of eyes from Persian kittens affected with alpha-mannosidosis were studied. Clinically the disease is characterized by progressive corneal and lenticular opacification. In addition there is asymmetry in shape and latency of signal conductions which were demonstrated by visual evoked potential studies. Morphological and histochemical studies revealed vacuolization of various ocular cell types which stained positively with Concanavalia ensiformis agglutinin (Con A) and wheat germ agglutinin (WGA). Biochemical studies illustrated low activity of acid alpha-mannosidase in cultured keratocytes and abnormal storage of partially degraded oligosaccharides in these cells, in vitreous humor and lens. This comprehensive study of ocular alpha-mannosidosis demonstrates enzyme deficiency which leads to abnormal storage of oligosaccharides in affected cells and is manifested by morphological alterations and functional impairment. 相似文献