Molecular variations

A molecular variation of plasma membrane has been reported by Puccia et al. Reduction of total lipids (XL) content and significant variations of triglyceride (TG) and phospholipids (PL) fractions were observed as a consequence of exposure of C. intestinalis ovaries to TBTCl solutions. In particular, an evident TG decrease and a PL increase were observed, which probably provoked an increment in membrane fluidity, because of the high concentration of long chain fatty acids and, as a consequence, PL. This could be a cell-adaptive standing mechanism toward the pollutants, as observed in Saccharomyces cerevisiae. Also the increase in the content of the polyunsaturated fatty acids (PUPA), important in the synthesis of compounds such as prostaglandin which are present in the ovary in a stress situation, was probably a consequence of a defense mechanism to the stress provoked by the presence of TBTCl. 

In a symmetrical octahedral system such as SFg, each polar S—F bond has a counterpart pointing in the opposite direction. The bond polarities cancel in pairs, leaving this molecule without a dipole moment. Example examines molecular variations on octahedral geometry. 

Lejambre, L.F. (1993) Molecular variation in trichostrongylid nematodes from sheep and catde. Acta Tropica 53, 331-343. 

In the 1950s, new methods of protein separation were developed that enabled the systematic study of molecular variation in many more human proteins. Starch gel electrophoresis allowed the separation of closely related protein variants by differences in charge and molecular size. Smithies (1955) detected the amazing polymorphism of haptoglobin. In later years the method was extended to the study of allozymes (enzyme polymorphisms). 

Luo, H.Y., Nie, P., Zhang, Y.A., Wang, C.T. and Yao, W.J. (2002) Molecular variation of Bothriocephalus acheilognathi Yamaguti, 1934 (Cestoda Pseudophyllidea) in different fish host species based on ITS rDNA sequences. Systematic Parasitology 52, 1 59-1 66. 

In Experiment 26, we looked at some molecular variations that acyclic organic molecules can take ... 

For the previous decade, Pauling s scientific work had been spotty at best. The research projects he had overseen—most notably a foray into the molecular roots of mental disease and a failed attempt to discover the mechanism of anesthesia—had produced little of value. His only lasting contribution came in 1961, when he and a coworker noted that molecular variations between the hemoglobins from different species could be correlated to the evolutionary distance between them. The more time that had elapsed... 

Newman PJ Platelet GPIIb-IIIa molecular variations and dioantigens. Thromb Haemostat 66 111-118,... 

Schroeder, W. A., and Huisman, T. H. J., Investigations of molecular variation in human fetal hemoglobin in the infant and in certain hematological conditions in the adult. Protides Biol. Fluids, Proc. Colhq. 17, 249-255 (1969). 

The structural requirements of the dopamine (and norepinephrine) transporter appear to be fairly rigid. There is very little molecular variation that is tolerated without significant loss of activity. The relatively limited information that is available, mostly from animal studies, can be summarized by considering the various areas of substitution for a general phenethylamine structure. These structure-activity relationships have been recently surveyed (132), and an extensive and comprehensive review by Biel and Bopp (133) covered the older literature. 

The natural molecular variation of hydrogenases in different cyanobacteria is a field to explore, both to understand the physiological functions of the respective enzymes, and to identify/find/construct a strain suitable of photobiological H2 production in a bioreactor. 

Molecular Variations in Homologous Series Vinylogues and Benzologues... 

CHAPTER 15 Molecular Variations Based on Isosteric Replacements... 

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