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Antiport mechanism

Na+-glucose, Na+-amino acid, Na+-phosphate, and NaMactate sym-porter mechanisms Na+-H+ antiporter mechanism first half of the proximal tubule... [Pg.317]

The melibiose carrier MelB of E. coli is a well-studied sodium symport system. This carrier is of special interest, because it can also use protons or lithium ions for cotransport. The projection structure of MelB has been solved at 8 A resolution [107]. The 12 TM helices are arranged in an asymmetrical pattern similar to the previously solved structure of NhaA, which, however, follows an antiport mechanism (Na+ ions out of the cell and H+ into the cell). [Pg.294]

Tamai, L, Takanaga, H., Maeda, H., Yabuuchi, H., Sai, Y., Suzuki, Y., and Tsuji, A., Intestinal brush-border membrane transport of monocarboxylic acids mediated by proton-coupled transport and anion antiport mechanisms, J. Pharm. Pharmacol, 49, 108, 1997. [Pg.353]

When incorporated into the phospholipid membrane of liposomes, compounds 114 and 115 increased the permeability to Na+ and Li+ ions, and ion transfer proceeded by a cation-cation antiport mechanism (Figure 25) [8.208]. [Pg.119]

Aluminum in micromolar concentrations was found to inhibit calcium pumping in endoplasmic reticulum. The Ca2+ ATPase activity of rat brain and cerebellum was remarkably reduced and mitochondria showed increased Ca2+ release in the presence of exactly estimated 50 pmol L-1 Al3+ [67]. Aluminum was found to be an important disrupter of intracellular calcium homeostasis, interfering also with the mitochondrial Ca2+ pump, as well as activating an Na+-K+ ATPase - the antiport mechanism of ion exchange in the plasma membrane, which regulates the Ca2+-Na+ antiporter exchange [67]. [Pg.159]

The MATE transporters are involved in MDR, preferentially to OCs, via a H or Na -coupled antiport mechanism. In humans, two genes encode MATEl and MATE2. MATEl is ubiquitous throughout the body, but is most abundant in the luminal membrane of the urinary tubules and bile canaliculi in the liver. By contrast, MATE2 is... [Pg.705]

The bouquet (91), incorporated into a phospholipid membrane of liposomes, increases the permeability of the membrane to Na" and Li. The ion transfer proceeds via a cation-cation antiport mechanism which has been established by Na and Li NMR spectroscopy <92AG(E)1637>. The incorporation of the bouquet molecule into several vesicular systems has been monitored by numerous techniques (UV, NMR, and CD spectroscopies, differential scanning calorimetry). It was concluded that different modes of incorporation take place and that several orientations of the bouquet coexist in the membranes <93JCS(P2)ioii>. [Pg.835]

This ionophore is able to carry selectively alkaline-earth cations through membrane phases by an antiport mechanism (m W 2h ) with a transport efficiency in favour of Ca versus Mg in biological membranes(3).Owing to its specificity, calcimycin is universally used as a tool to investigate the role of the second messenger calcium in physiological processes. [Pg.99]

Chao, Y Fu, D. Kinetic study of the antiport mechanism of an Escherichia coli zinc transporter, ZitB. J. Biol. Chem. 2004, 279, 12043-12050. [Pg.207]

FIGURE 9.4 Mechanisms for facilitated transport, (a) Uniport mechanism, (b) Symport mechanism, (c) Antiport mechanism... [Pg.106]

The molecular mechanisms by which growth factors exert their influence remain largely unknown. However, on growth factor-receptor interaction, the intrinsic kinase activity catalyses the phosphorylation of target cytoplasmic proteins only on tyrosyl residues. These tyrosine-specific protein phosphorylations may initiate a cascade of biochemical events which ultimately promote DNA synthesis and cell division. Other consequences of the binding of growth factors to their receptors include the hydrolysis of phosphoinositides, a sustained rise in cytoplasmic pH through the activation of an Na /H antiport mechanism in the plasma membrane and a transient rise in cytoplasmic free Ca concentration. However, EGF-... [Pg.125]

PAPS is synthesized within the cytosol of cells. Sulfate enters cells through an active transport process [4]. A sulfate transporter has been identified which is mutated in diastrophic dysplasia, a disease characterized by undersulfation of proteoglycans in cartilage [9]. For utilization by Golgi sulfotransferases, PAPS must cross a lipid bilayer. A PAPS translocase, which functions through an antiport mechanism has been characterized at the biochemical level [10]. [Pg.1363]

In the Organophosphate Phosphate Antiporter (OPA) family (2. A. 1.4), most members preferentially catalyze substrate substrate antiport, but they can also catalyze substrate H symport, and some preferentially seem to use a symport rather than an antiport mechanism. Also, in the Nitrate/ Nitrite Porter (NNP) family (2.A. 1.8), members of similar sequence can catalyze either uptake, efflux, or NO j NO exchange. Finally, members of the Organocation Transporter (OCT) family in animals (2.A.1.19) appear to be mechanistically promiscuous, catalyzing substrate uptake, export, exchange, and/or uniport. Sometimes the mechanism and substrate H stoichiometry depends on... [Pg.59]


See other pages where Antiport mechanism is mentioned: [Pg.92]    [Pg.18]    [Pg.193]    [Pg.162]    [Pg.165]    [Pg.92]    [Pg.89]    [Pg.11]    [Pg.213]    [Pg.58]    [Pg.310]    [Pg.36]    [Pg.439]    [Pg.564]    [Pg.580]    [Pg.9]    [Pg.165]    [Pg.239]    [Pg.316]    [Pg.309]    [Pg.732]    [Pg.1144]    [Pg.1145]    [Pg.1500]    [Pg.59]   
See also in sourсe #XX -- [ Pg.51 , Pg.245 , Pg.294 , Pg.296 ]

See also in sourсe #XX -- [ Pg.51 , Pg.245 , Pg.294 , Pg.296 ]




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