Lipid dependence

In this chapter we will review the recent investigations of the structure of both the a and P subunit, and the function of gastric H,K-ATPase. We will proceed from a brief overview of the tissue distribution to a successive discussion of structure, kinetics, transport properties, lipid dependency, solubilization and reconstitution, and inhibitors of H,K-ATPase that may label functionally important domains of the enzyme. 

Interaction of the liposomal lipids with cellular lipid bilayers or other lipid bilayers in the body (e.g. skin lipids) depends on the nature of the lipids in the liposome. In order to... 

The effects of storage on lipids depend on potato variety (Mondy et al., 1963). Tuber storage at 4°C resulted in an initial small increase in total fatty acid content (Dobson et al., 2004). Prolonged storage resulted in a fall to the initial values detected close to harvest. The content... 

Incorporation of different fatty acids into lipids depends on the relative abundance of their CoA derivatives and their acyl-transferase )< , values. The synthetic enzymes which form membrane phospholipids may select the acid by molecular features not in accord with the optimal physiological properties of the products (110), resulting in the formation of membranes which do not function adequately. 

The subcellular distribution of lipid-dependent, glycosylation reactions has also been investigated in a number of plant systems. In plant cells, the situation is, however, more complicated, as their membranes often have the capability to transfer activated sugars, not only to lipid-bound saccharides201-203 and to proteins,4B-204-2,)li but also to cell-wall... 

The best known inhibitors of glycosylation of proteins interfere with the lipid-dependent steps.35,228 Substances that specifically block reactions taking place after the transfer of the oligosaccharide to the protein are little known. As several, incompletely (or differently) glycosylated, viral glycoproteins arc still biologically active (see Section IV), these substances would escape the screening procedure based on... 

Brzeska, H. Young, R. Knaus, U. Korn, E.D. Myosin I heavy chain kinase cloning of the full-length gene and acidic lipid-dependent activation by Rac and Cdc42. Proc. Natl. Acad. Sci. USA, 96, 394-399 (1999)... 

Biliary cholesterol is entirely unesterified and flows into the small intestine as a component of bile. The other major components of bile are phosphatidylcholine (lecithin) and bile acids. Absorption of cholesterol and other lipids depends on their ability to form micelles within the intestinal lumen. 

There is debate in the literature about the relative importance of lipid-dependent mechanisms versus pleiotropic effects of statins. Several lines of evidence suggest that the pleiotropic effects of statins are clinically relevant ... 

Gj, G0, Gq). As a result, the inner leaflet of the plasma membrane is the source of a variety of chemical mediators that are released as a consequence of receptor activation. These mediators include inositol 1,4,5-trisphosphate (IP3) and 1,2-diacylglycerol (DAG), which are both products of Pi-specific phospholipase C (Fig. 6-23) and arachidonic acid, which is an unsaturated fatty acid product of phospholipase A2 and phosphatidate (a product of phospholipase D). IP3 induces the release of Ca2+ ions from intracellular endoplasmic reticulum stores. DAG is a known activator of a lipid-dependent serine/threonine protein kinase (protein kinase C). 

Because fatty acids derived from natural sources are present in a mixture, an ideal analysis method for these molecules should be applicable to mixtures without requiring a prior separation or derivatization. Mass spectrometry is an excellent tool for determining the structure of fatty acids present in a mixture. It is possible to determine not only the molecular weight and thus the elemental composition but also, in most cases, the nature and position of the branching and the other substituents on the carbon chain. [268,269] Furthermore, such an analysis requires low quantities ranging from 10 pg to 100 ng of total lipid, depending upon the analysed sample, the ionization method used and the configuration of the spectrometer. [270,271]... 

PDGF, platelet-derived growth factor PDGF-RTK, platelet-derived growth factor receptor tyrosine kinase PDPK, phosphatidylinositol lipid-dependent PK... 

Alesenko et al., studied the effect of antioxidants on the genetic apparatus activity [41-43]. The authors showed that bioantioxidants are able to affect the cell lipids composition and change the activity of lipid-dependent enzymes of synthesis and reparation of DNA and affect the activity of chromatin. 

The specific binding of a PH domain to lipids depends not only on the structure of the parent protein but also on the protein environment surrounding the membrane lipids it will bind. Studies using GFP-PH domains to identify lipid microdomains have shown that some lipids are inaccessible to PH domain binding and emphasize the need to characterize the binding specificity of the PH domain prior to engaging in in vivo studies (Balia et al., 2000 Balia and Varnai, 2002). 

Mukherjee A, Arnaud L, Cooper JA. Lipid-dependent recruit-... 

Oat lipids may contain 55-90% neutral lipids depending on the grain fraction (Table 27). Oat bran endosperm contains significantly higher amounts of both glycolipids and phospholipids. The phospholipid content of oat hull is lower than that of the other fractions. There is considerable variation in the reported proportions of individual lipid classes, but the major component of the neutral lipids is TAG (35-85%) (125). The free fatty acid content of oat lipids is in the range of 2-11%. 

Lipoproteins contain protein subunits along with lipids. Depending upon density and lipid compound they are further classified as VLDL. LDL and HDL. 

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