Structural Characterization of the NodD Transcription Factor

Abstract Using computer analysis and modeling we studied NodD transcription factor which controls expression of nodulation genes of symbiotic nitrogen-fixing bacteria. On the basis of the amino acid sequences it was predicted that in the secondary structure of NodD protein it must be present ten alpha helices and three beta sheets which form two do mains after folding. Since NodD acts in oligo meric mode, it was analy zed all four known for other similar factors of transcription ways of assembly into dime rs. Using molecular docking the probable mechanism o f NodD act ivation by binding of low molecular weight inducer (on the model o f luteolin) was clarified

Effect of Melatonin on Lipid Barrier in Rats' Skin

Abstract In this work we studied the effect of intraperitoneal ad min istration of melatonin in a dose of 1 mg per kg on lip ids and microstructure of rats' skin. A single inject ion of melatonin induced a change in lipid profile most notably in phospholipids and triacylglycerol fractions which contents varied oscillatory in opposite each other with a maximu m divergence at 3 hours. By 24 hours there was a significant increase in triglycerides, and after 48 hours the lipid profile approached the init ial values. After regular daily ad ministration of melatonin for 6 days, the contents of almost all lipid fractions were significantly reduced (most in triacylg lycerols and phospholipids) with growing level of free fatty acids. By 21st day the contents of lip ids in the skin increased again, but did not reach the initial values. Reduction of lip id level was accompanied by pro minent degenerative changes in the microstructure of the skin by the 6th day of experiment. In general, the administration of melatonin in any way caused the changes in skin's lipid profile but after a single introduction parameters of lip id spectrum in two days were restored to their in itial values, and a regular ad min istration for 6 days led to sustained changes in lip id profile and structure of the skin