Cytoplasm, cell

Considerable work has been done to try to explain why quats are antimicrobial. The following sequence of steps is beheved to occur in the attack by the quat on the microbial cell (/) adsorption of the compound on the bacterial cell surface (2) diffusion through the cell wall (J) binding to the cytoplasmic membrane (4) dismption of the cytoplasmic membrane (5) release of cations and other cytoplasmic cell constituents (6) precipitation of cell contents and death of the cell. 

Cytoplasm Cell walls Cytoplasm Cell walls... 

Cuthbertson KS, Whittingham DG, Cobbold PH 1981 Free Ca2+ increases in exponential phases during mouse oocyte activation. Nature 294 754—757 Day ML, Johnson MH, Cook DI 1998 A cytoplasmic cell cycle controls the activity of a K+ channel in pre-implantation mouse embryos. EMBO J 17 1952—1960 Flach G, Johnson MH, Braude PR, Taylor RA, Bolton VN 1982 The transition from maternal to embryonic control in the 2-cell mouse embryo. EMBO J 1 681-686 Howlett SK 1986 A set of proteins showing cell cycle-dependent modification in the early mouse embryo. Cell 45 387-396... 

Borer RA, Lehner CF, Eppenberger HM, Nigg FA (1989) Major nucleolar proteins shuttle between nucleus and cytoplasm. Cell 56 379-390... 

The final principal component of the cell is the nucleus. This is located in the center of the cell and is surrounded by a double membrane, the outer layer being derived from the ER of the cytoplasm and the inner layer coming from the nucleus itself. The two leaflets of the double membrane are fused in places, producing nuclear pores that enable the transfer of macromolecules from the cytoplasm to the nucleus. Two important components of the nucleus are chromatin and the nucleolus. Chromatin represents polymers of DNA complexed with protein. The nucleolus is a complex substructure, composed of ribonucleoprotein granules, that controls the synthesis of RNA destined to form the ribosomes of the cytoplasm. Cells engaged heavily in protein synthesis have... 

Transcriptional activators. Many proteins serve as activators of transcription, causing larger increases in rate over those observed with TBP alone. Some of these are listed in Table 28-2.338a The table also lists two proteins (Spl and NF1), and the DNA sequence CCAAT, which control constitutive or continuously active genes. A large group of transcription factors are active in development. Receptors may be resident in cytoplasm, cell membrane or nucleus, as indicated in Table 28-2. Some cytoplasmic factors are latent, becorn-... 

Cui, C., Smith, D.O. and Adler, J. (1995) Characterization of mechanosensitive channels in Eschericia cofi cytoplasmic cell membrane by whole-cell patch clamp recording. Journal of Membrane Biology 144 31-42... 

Substrates bind to P-gp while they are associated with the plasma membrane this process is possibly the most important aspect of P-gp-mediated efflux activity to appreciate. By using fluorescent dye esters, it was shown that P-gp interacts with its substrates within the plasma membrane. As these dye esters cross the membranes, esterases quickly hydrolyze the esters to their free acid form in the cytoplasm. Cells expressing P-gp showed no accumulation of the free acid dye in the cytoplasm clearly illustrating that P-gp can efflux substrates directly from the membrane (129). Additionally, P-gp can bind to substrates at the inner leaflet—cytosolic interface as demonstrated in studies with the P-gp substrate rhodamine 123 (133). It was shown that P-gp does not influence drug concentration in the exofacial leaflet (134), thus implying that P-gp only binds compounds from either within the inner leaflet or at the inner leaflet—cytosolic interface. These findings clearly show that the behavior of the substrate/inhibitor within the lipid barrier is likely to be a primary determinant of P-gp-mediated efflux activity. This separates P-gp from traditional transporters in which binding of the substrate to the active site in an enzyme-like fashion is the primary determinant of transport activity. 

Prokaryotic cells have much simpler structures when compared with the simplest eukaryotes, such as yeast, fungi or algae. They have no nucleus enveloped by a membrane and no vacuoles, which are known to possess many PolyPs in eukaryotic cells. The compartmen-talization of biochemical processes is not well developed in prokaryotic cells. However, PolyPs are found in all main compartments of the bacterial cell, i.e. cytoplasm, cell surface, periplasm and plasma membrane. 

When a small portion of the mycelium is mounted in lo per cent, alcohol and observed under the high-power objective, it will be noted that each hypha has a transparent wall and" protoplasmic contents and is divided by transverse septa into a number of cells. Each cell contains protoplasm, which is differentiated into cytoplasm (cell... 

Cytoplasm-cell membrane translocation Cytoplasm-to-Nudeus Translocation GPCR signaling Micronucleus... 

The complex permittivity of the cell, Sp is a function of the dielectric properties of membrane and cytoplasm, cell membrane internal... 

Cell Wall Cell. Membrane Cytoplasm Cell Nuclear region Ribosome... 

Transcription and translation are coupled in the cytoplasm of prokaryotes. In eukaryotes, transcription of DNA and subsequent processsing of the messenger RNA transcript both occur in the nucleus, while translation of the mature mRNA template occurs in the cytoplasm. Cell-free systems lack mechanisms for mRNA processing, and therefore require fully matured... 

Orientation of the Mitotic Spindle Is Linked to Cytoplasmic Cell-Asymmetry Factors... 

SIRT2 Nucleus, cytoplasm Cell cycle regulation... 

The most important lipophilic antioxidant that acts in eucary-otic cells to protect unsaturated lipids against free radical damage is vitamin E, especially a-tocopherol. Along with P-carotene and coenzyme Q, it protects the structure and integrity of biomembranes, such as the cytoplasmic cell membrane (or plasmolema) and intracellular membranes of organelles (nucleus, mitochondria, lysosome and endoplasmic reticulum). It k ako employed in the protection of lipoproteins present in plasma. It is transported in the bloodstream by association with the lipid phase of low density Hpoprotein (LDL) particles (see Section 3.6.1). Each LDL particle contains six molecules of vitamin E. 

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