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661.
Molecular Biology Reports - Coriander (Coriandrum sativum L.) is a well-known spice and aromatic crop cultivated globally. Stem gall disease is one of the major constraints for its leaf and seed... 相似文献
662.
Diaminopimelate decarboxylase (EC 4.1.1.20) ofMicrococcus glutamicus ATCC 13059 was purified to homogeneity. The enzyme had an apparent molecular weight of 191,000 as determined by gel filtration
on Sephadex G-200. At protein concentrations of 20 and 10 μg per ml and in the absence of pyridoxal-5′-phosphate, it dissociated
into a species of molecular weight 94,000. The polypeptide chain molecular weight as determined by sodium dodecyl sulphate
Polyacrylamide gel electrophoresis was 100,000. TheK
m formeso diaminopimelate was 0.5 mM and that for pyridoxal-5′-phosphate was 0.6 μI. Sulphydryl groups and pyridoxal-5′-phosphate were
essential for activity and stability. The enzyme was inhibited significantly by L-lysine and DL-aspartic β-semialdehyde. 相似文献
663.
Analysis of intracellular and extracellular lysine concentration during lysine fermentation byMicrococcus glutamicus AEC RN-13-6/1 indicated that lysine excretion occurs against a concentration gradient towards the end of the fermentation
period. The capacity to excrete lysine against a concentration gradient may be a factor contributing to the high yield of
lysine. 相似文献
664.
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666.
Foliage and tuber fresh matter and chlorophyll content in cvs. Atom alue, Multa, Kufri, Desiree and Patrones were decreased with the increase in soil acidity. However, tuberization was enhanced at pH 5.5 and decreased significantly at pH 4.5 in all cultivars tested. At pH 4.5 the specific mass of all the cultivars was slightly increased. The highest content of reducing sugars and proteins was found at pH 5.5. No definite pattern was observed in total glycoalkaloids content under different acidic range. 相似文献
667.
Rajeev Kapila Renjith Sebastian Vivek Phani Varma D Rohit Sharma Meena Kapasiya Vamshi Salingati Suman Kapila Ajay K. Dang 《Microbiology and immunology》2013,57(11):778-784
The present investigation aimed at identifying the abilities of three different species of probiotic lactobacilli to modulate cellular immune responses in mouse neutrophils and macrophages in vivo over a study period of 60 days. Neutrophil respiratory burst enzymes (cytochrome c reductase and MPO) showed remarkable increased activity (P ≤ 0.01) after consumption of milks fermented by different species of probiotics over 30 and 60 days of feeding trials. Enzyme activities (β‐galactosidase and β‐glucuronidase) and nitric oxide production also increased considerably (P ≤ 0.01) in macrophages, both in peritoneal fluid and in enriched cell cultures. The effects of enhanced enzyme activities were corroborated by simultaneous increases in the phagocytic activities of neutrophils and macrophages. The increases in cellular functions were invariably maximal during the first 30 days of study and were maintained, but did not increase, over the next 30 days. Further, Lactobacillus helveticus‐fed groups were most effective at modulating neutrophil functions whereas Lactobacillus paracasei‐fed groups were more potent at enhancing macrophage functions. Together, our results indicate that probiotics have strain specific effects on stimulating cellular functions while not causing excessive stimulation of the immune system over longer feeding periods, thereby resulting in maximum and stable health benefits. 相似文献
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669.
Aaditya Narasimhan Jigisha Rohit Kapila Abhishek Meena Santhosh Nagaraj Guru Prasad 《Journal of evolutionary biology》2023,36(4):730-737
Sexual selection is a major force influencing the evolution of sexually reproducing species. Environmental factors such as larval density can manipulate adult condition and influence the direction and strength of sexual selection. While most studies on the influence of larval crowding on sexual selection are either correlational or single-generation manipulations, it is unclear how evolution under chronic larval crowding affects sexual selection. To answer this, we measured the strength of sexual selection on male and female Drosophila melanogaster that had evolved under chronic larval crowding for over 250 generations in the laboratory, along with their controls which had never experienced crowding, in a common garden high-density environment. We measured selection coefficients on male mating success and sex-specific reproductive success, as separate estimates allowed dissection of sex-specific effects. We show that experimental evolution under chronic larval crowding decreases the strength of sexual and fecundity selection in males but not in females, relative to populations experiencing crowding for the first time. The effect of larval crowding in reducing reproductive success is almost twice in females than in males. Our study highlights the importance of studying how evolution in a novel, stressful environment can shape adult fitness in organisms. 相似文献
670.
New fluorescent polymeric materials were synthesized by grafting the nucleobase cytosine on to the backbone of agarose and κ-carrageenan, employing a rapid water based method under microwave irradiation using potassium persulphate (KPS) as an initiator. The emission spectrum of the modified agarose and κ-carrageenan recorded in aqueous solution (5 × 10−5 M) exhibited emission maxima (λem,max) at 348 nm by excitation at 266 nm. The emission intensity was enhanced by ca. 104% and 60% compared to that of pure cytosine solution of the same concentration. When the concentration of the pure cytosine solution is made equivalent to the concentration of the cytosine molar component (3.09 × 10−5) and (3.5 × 10−5) present in 5 × 10−5 M solution of modified agarose and κ-carrageenan, respectively, then ca. 143% and 81% enhancement in emission intensity was observed. The remarkable fluorescent activity of the agarose-cytosine derivative may have potential uses as sensor in various applications. 相似文献