It has been proposed that certain stress conditions such as low temperature could cause injury to vacuolar membranes
in plant cells [32, 33].
Each individual symbiont is then housed within a host gastrodermal cell, contained within a host-derived vacuolar membrane
, or symbiosome (Wakefield and Kempf, 2001).
For measurement of bafilomycin [A.sub.1]-sensitive ATPase activity in vacuolar membranes, reaction mixes contained in millimolar: 30 Hepes (buffered with BTP to pH 7.5), 5 Mg[SO.sub.4], 5 PEP, 5 ATP (buffered to pH 7.5 with BTP using Dowex 50W), 4.5 units of pyruvate kinase, 0.12 [micro]L [mL.sup.-1] Triton X- 100 and 15 to 20 [micro]g of membrane protein.
Samples were denatured by boiling for 4 min (vacuolar membranes) or incubation at 30 [degrees] C for 2 min (to prevent aggregation of plasma membrane proteins due to boiling) and separated on polyacrylamide gels (1.41 mol [L.sup.-1]) according to Laemmli (1970).
During an action potential, the plasma membrane depolarizes to approximately 0 V and the vacuolar membrane hyperpolarizes to approximately -0.050 V.
The specific conductances of the plasma membrane and vacuolar membrane at rest are 0.83 siemens [m.sup.-2] (S[m.sup.-2]) and 9.1 S [m.sup.-2], respectively.
Arabidopsis thaliana MTP1 is a Zn transporter in the vacuolar membrane
, which mediates Zn detoxification and drives leaf Zn accumulation.
Khotimchenko, "Fatty acid composition of lipids from the vacuolar membranes
of the roots of root vegetables," Russian Journal of Plant Physiology, vol.
If the accumulation body is a lysosome or a trash dump, host sym32 may be transported from the vacuolar membranes
, across the dinoflagellate cell wall, and into a degradative pathway within the dinoflagellate.
The V-type ATPases can occur in the plasma membrane of eukaryotes (but are more commonly associated with vacuolar membranes
) and consist of at least 11 subunits and a molecular mass approaching [10.sup.6] Da.
Historically, these layers have been referred to by a variety of terms, including the periplast (Dodge and Crawford, 1970; Kevin et al., 1969; Palincsar et al., 1988; Taylor, 1968; Trench and Blank, 1987), the amphiesma (Schoenberg and Trench, 1980a; Thinh et al., 1986), the theca (Battey, 1992; Taylor, 1971), the vacuolar membranes
(Colley and Trench, 1983), or simply the cell covering (Tripodi and Santisi, 1982).