Membrane integration

He/minthosporium (15). The mode of action is considered to be inhibition of the enzyme NADPH-cytochrome C reductase, which results in the generation of free radicals and/or peroxide derivatives of flavin which oxidize adjacent unsaturated fatty acids to dismpt membrane integrity (16) (see Enzyme inhibitors). 

Two mechanisms are operating alone or in concert to minimize the antibiotic concentration at the intracellular target site Downregulation of the expression of the pore proteins, also called porins, and upregulation of one or a set of several unspecific efflux pumps. However, the impact of these mechanisms on the resistance is low, since due to the essential function of porins for uptake of nutrients their reduction is limited and to avoid disturbances of membrane integrity due to extensive oveiproduction of mdr efflux pumps these are subjected a strict regulation. 

Henry, M.A., Nodes, E.E., Gao, D., Mazur, P., Critser. J.K. (1993). Cryopreservation of human spermatozoa. IV. The effects of cooling rate and warming rate on the maintenance of motility, plasma membrane integrity, and mitochondrial function. Fertil. and Steril. 60,911-918. 

In both plant (e.g. [57]) and animal (e.g. [86]) cell systems, cellular respiration has been shown to be a more sensitive indicator of system response to hydro-dynamic stress than membrane integrity, suggesting that intracellular enzymes and/or organelles may be affected at stress levels lower than those required to cause membrane damage. 

Datura stramonium rheogniometer oscillatory membrane integrity non-growth [31]... 

Morinda citrifolia recirculating flow capillary laminar/turbulent membrane integrity morphology non-growth [54, 120]... 

Daucus carota Couette viscometer laminar regrowth mitochondrial activity membrane integrity cell lysis (cell number) non-growth (sterile) [57, 69]... 

Cathanthus roseus Nicotiana tabacum Cinchona robusta Tabernaemontana divaricata 3-1 STR (2 1 wv) D 4.5 cm batch and chemostat N 2.5 -16.7 s Q 0.33 wm t < 30 d biomass production total organic carbon extracellular protein membrane integrity substrate consumption [107]... 

The well-known fact that in irreversibly damaged cells, respiratory control is lost and is accompanied by oxidation of cytochromes a and as, as well as NADH (Taegtmeyer et al., 1985), was originally thoug it to be due to substrate deficiency (Chance and Williams, 1955) but may be due to an enzymatic defect resulting in an inability to metabolize NADH-linked substrates (Pelican etal., 1987). It seems likely therefore that return of function is dependent on preservation of mitochondrial membrane integrity, and the structure and activities of respiratory chain (R.C) complexes I-IV (Chance and Williams, 1955). 

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