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51.
A homoserine auxotroph strain of Corynebacterium glutamicum accumulates storage compound trehalose with lysine when limited by growth. Industrially lysine is produced from C. glutamicum through aspartate biosynthetic pathway, where enzymatic activity of aspartate kinase is allosterically controlled by the concerted feedback inhibition of threonine plus lysine. Ample threonine in the medium supports growth and inhibits lysine production (phenotype-I) and its complete absence leads to inhibition of growth in addition to accumulating lysine and trehalose (phenotype-II). In this work, we demonstrate that as threonine concentration becomes limiting, metabolic state of the cell shifts from maximizing growth (phenotype-I) to maximizing trehalose phenotype (phenotype-II) in a highly sensitive manner (with a Hill coefficient of 4). Trehalose formation was linked to lysine production through stoichiometry of the network. The study demonstrated that the net flux of the population was a linear combination of the two optimal phenotypic states, requiring only two experimental measurements to evaluate the flux distribution. The property of linear combination of two extreme phenotypes was robust for various medium conditions including varying batch time, initial glucose concentrations and medium osmolality. 相似文献
52.
Shabeesh Balan Sarada lekshmi Koramannil Radha Sanish Sathyan Joseph Vijai Moinak Banerjee Kurupath Radhakrishnan 《Gene》2013
The human major vault protein (MVP) has been implicated in the development of drug resistance in cancer cells. Over expression of MVP has also been reported in brain tissue samples from antiepileptic drug (AED)-resistant human focal epilepsies. To investigate the relationship between single nucleotide polymorphisms (SNPs) involving the MVP gene and AED-resistance, we compared the distribution of three SNPs in the MVP gene, rs4788187, rs3815824 and rs3815823, among 220 patients with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) (prototype of AED-resistant epilepsy syndrome), 201 patients with juvenile myoclonic epilepsy (JME) (prototype of AED-responsive epilepsy syndrome) and 213 ethnically matched non-epilepsy controls. All the patients and controls were residents of the South Indian state of Kerala for more than three generations. We did not find any significant difference in allele and genotypic frequencies of the studied SNPs between AED-resistant and AED-responsive cohorts, and between AED-resistant and AED-responsive cohorts independently and pooled together when compared with the controls. We conclude that rs4788187, rs3815824, rs3815823 variants of the MVP gene are associated neither with predisposition for epilepsy nor with AED-resistance in the population that we have studied. Our results suggest the need for further research into the link between MVP and AED-resistance. 相似文献
53.
Protein production during sexual maturation or after allatectomy (followed by juvenile hormone replacement therapy) has been examined in the long hyaline glands, short hyaline glands, white glands, and seminal vesicles, which make up the accessory gland complex of male Melanoplus sanguinipes. During maturation, the amount of protein in the long hyaline glands increases about 14-fold, and in each of the other components between 5- and 6-fold. Most protein accumulates between days 3 and 5, and this is reflected in high levels of incorporation of radiolabelled leucine in this period. The components show differential sensitivity to the effects of allatectomy. After this operation, the protein content of, and incorporation of radiolabel into, the long hyaline glands remain near the day 0 level. In the white glands and short hyaline glands, allatectomy also has a marked, though less severe, effect on protein synthesis and accumulation. The seminal vesicles are least affected by allatectomy and continue to accumulate protein (though more slowly) to about 60% of the normal level by day 10. Juvenile hormone compounds applied topically to allatectomized insects on day 2 restored the ability of the gland components to accumulate proteins, though to differing degrees. JHI is the most effective compound, stimulating synthesis and accumulation of protein to near normal levels by day 10, whereas application of JHIII or Stauffer's synthetic JH led to only partial restoration of protein synthesis in the glands. 相似文献
54.
55.
Viswanathan Kasi Kumaresan Venkatesh Sannasimuthu Anbazahan Paray Bilal Ahmad Al-Sadoon Mohammad K. Arockiaraj Jesu 《Molecular biology reports》2019,46(4):3877-3886
Molecular Biology Reports - Schizophyllum commune is a well-known mushroom forming fungi which is an edible one due to its nutritive value. It exhibits a special wood degrading mechanism to grow in... 相似文献
56.
Eliahu Heldman Ayala Balan Ora Horowitz Sarit Ben-Zion Michael Torten 《FEBS letters》1985,180(2):243-248
Antiparaoxon immune sera were employed in a new immunoassay based on competition between acetylcholinesterase and antibodies for the binding ofparaoxon. Unlike radioimmunoassay, the new assay described herein can be extended to predict the feasibility of antibodies to confer in vivo protection of acetylcholinesterase against organophosphate poisoning. The toxicity of paraoxon was reduced in mice which were pre-injected with the immune sera. 相似文献
57.
A cell culture that preserves its phenotype up to the 20th passage was obtained from mouse submandibular salivary glands.
An analysis of the heterogeneous culture indicates the existence of several morphological types of cells, including small,
densely packed cells of cuboidal or polygonal shapes and large, rounded cells. Epithelial cells of the submandibular gland
cultured for several weeks were able to form tubular structures. Our studied cell culture of glandulocytes (cells of glandular
epithelium) was represented by K19- and NGF-positive cells. It is important to note that, using both immunocytochemical staining
and PCR, the expression of genes that encode the proinsulin and insulin proteins is revealed in the studied cell population. 相似文献
58.
Kousik?Chandra Venkatesh?Ramakrishnan Yogendra?Sharma K.?V.?R.?CharyEmail author 《Journal of biological inorganic chemistry》2011,16(1):81-95
Neuronal calcium sensor-1 (NCS-1) interacts with many membranes and cytosolic proteins, both in a Ca2+-dependent and in a Ca2+-independent manner, and its physiological role is governed by its N-terminal myristoylation. To understand the role of myristoylation
in altering Ca2+ response and other basic biophysical properties, we have characterized the Ca2+ filling pathways in both myristoylated (myr) and non-myristoylated (non-myr) forms of NCS-1. We have observed that Ca2+ binds simultaneously to all three active EF-hands in non-myr NCS-1, whereas in the case of myr NCS-1, the process is sequential,
where the second EF-hand is filled first, followed by the third and fourth EF-hands. In the case of myr NCS-1, the observed
sequential Ca2+ binding process becomes more prominent in the presence of Mg2+. Besides, the analysis of 15N-relaxation data reveals that non-myr NCS-1 is more dynamic than myr NCS-1. The overall molecular tumbling correlation time
increases by approximately 20% upon myristoylation. Comparing the apo forms of non-myr NCS-1 and myr NCS-1, we found the possibility
of existence of some substates, which are structurally closer to the holo form of the protein. There are more such substates
in the case of non-myr NCS-1 than in the case of the myr NCS-1, suggesting that the former accesses larger volumes of conformational
substates compared with the latter. Further, the study reveals that the possibility of Ca2+ binding simultaneously to different parts of the protein is more favourable in non-myr NCS-1 than in myr NCS-1. 相似文献
59.
Joseph Kuo-Hsiang Tang Semion K. Saikin Sai Venkatesh Pingali Miriam M. Enriquez Joonsuk Huh Harry A. Frank Volker S. Urban Alán Aspuru-Guzik 《Biophysical journal》2013
Green photosynthetic bacteria adjust the structure and functionality of the chlorosome—the light-absorbing antenna complex—in response to environmental stress factors. The chlorosome is a natural self-assembled aggregate of bacteriochlorophyll (BChl) molecules. In this study, we report the regulation of the biogenesis of the Chlorobaculum tepidum chlorosome by carbon assimilation in conjunction with temperature changes. Our studies indicate that the carbon source and thermal stress culture of C. tepidum grows slower and incorporates fewer BChl c in the chlorosome. Compared with the chlorosome from other cultural conditions we investigated, the chlorosome from the carbon source and thermal stress culture displays (a) smaller cross-sectional radius and overall size, (b) simplified BChl c homologs with smaller side chains, (c) blue-shifted Qy absorption maxima, and (d) a sigmoid-shaped circular dichroism spectra. Using a theoretical model, we analyze how the observed spectral modifications can be associated with structural changes of BChl aggregates inside the chlorosome. Our report suggests a mechanism of metabolic regulation for chlorosome biogenesis. 相似文献
60.
Pablo Moreno Stephan Beisken Bhavana Harsha Venkatesh Muthukrishnan Ilinca Tudose Adriano Dekker Stefanie Dornfeldt Franziska Taruttis Ivo Grosse Janna Hastings Steffen Neumann Christoph Steinbeck 《BMC bioinformatics》2015,16(1)