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401.
The transport of α-methyl-D-glucoside and two aminoacids, L-phenylalanine and L-leucine by a temperature sensitive fatty acid
requiring mutant ofSalmonella typhimurium was studied under conditions of supplementation withcis or trans-unsaturated fatty acids. The results of such experiments definitely establish a relationship between the fatty acids
composition of the membrane and the transport property of the cells. Cells grown in the presence of trans-unsaturated fatty
acids cannot transport so efficiently as compared to the cis-unsaturated fatty acid-grown cells except linolelaidic acid,
atrans-trans-unsaturated fatty acid. Protein: phospholipid ratio of the membrane also varies significantly under such conditions. The
affinity of L-phenylalanine transport carrier for the substrate changes remarkably in cells grown in the presence of differentcis or trans-unsaturated fatty acids and indicate the possible role of membrane lipids in membrane assembly as well as regulation
of the activity of L-phenylalanine transport system. 相似文献
402.
Borah Ankita Deb Bornali Chakraborty Supriyo 《International journal of peptide research and therapeutics》2021,27(1):229-244
International Journal of Peptide Research and Therapeutics - Antimicrobial peptides (AMPs) are small sized protein molecules which play a crucial role in host inborn immune framework. AMPs with... 相似文献
403.
A plasmid vector pBK2 was tested for maintenance in Corynebacterium acetoacidophilum and found to be 100% stable for 90 generations. In co-culture experiments in absence of any selection pressure it was able to cause washout of plasmid free cells. Deletion mutagenesis of the plasmid was done to identify the regions of DNA responsible for its stable maintenance. This led to the identification of a region of DNA in pBB1, an endogenous plasmid used in the construction of pBK2, which is responsible for providing a growth rate advantage to the plasmid containing cell in co-culture with plasmid-free cells. To explain this observed stability we postulate the production of a “growth-inhibiting factor” by the plasmid-containing cells. Inclusion of a death rate term for the plasmid free cells in the computer simulation of the growth kinetics in a chemostat successfully predicts, depending upon the magnitude of the kinetic parameters, a stable coexistence of the two or washout of the plasmid-free cells, an observation that matches the experimental data. Because of its stable maintenance and its ability to select against plasmid-free cells this host-vector system is a natural candidate for cloning and use in large-scale fermentations. 相似文献
404.