Protein-lipid interaction

Gómez‐Fernández, Juan C.; Goñi, Félix M.; Bach, D.; Restall, Colin J.; Chapman, D.

doi:10.1016/0005-2736(80)90031-0

Cited by 102 publications

(37 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fluorescence experiments carried out at 5O"C, i.e., well above the main T, transition temperature of pure DPPC, indicate that the value of the polarisation index P increases as the UQ3 contents increases, as expected for intrinsic molecules [6]. UQ,,, is also different in this respect.…”

Section: Febs Letters September 1981mentioning

confidence: 70%

See 1 more Smart Citation

On the interaction of ubiquinones with phospholipid bilayers

Alonso¹,

Gómez‐Fernández

Aranda

et al. 1981

FEBS Letters

View full text Add to dashboard Cite

Section: Febs Letters September 1981mentioning

confidence: 70%

“…Peak areas were measured by weighing paper cut-outs of the peaks. Other details of the technique were as in [6]. The phospholipid contents of the pans were determined as lipid phosphorus according to [ 71.…”

Section: Introductionmentioning

confidence: 99%

On the interaction of ubiquinones with phospholipid bilayers

Alonso¹,

Gómez‐Fernández

Aranda

et al. 1981

FEBS Letters

View full text Add to dashboard Cite

“…Earlier, we tested the ability of the boundary lipid model to fit these data, using the assumption of two independent lipid domains (13 [1] in which Z1 is the intensity-weighted mol fraction of DPH lo- ATPase content ofpartially delipidated SR membranes. Data at 10 (e), 25 (A), and 370C (n) have been reported (13). New data are presented for 15 (o), 20 (A), and 300C (n).…”

Section: Resultsmentioning

confidence: 99%

Ordered and disordered phospholipid domains coexist in membranes containing the calcium pump protein of sarcoplasmic reticulum.

Lentz¹,

Clubb²,

Barrow³

et al. 1983

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Data are presented that lead to an alternative model for the organization and molecular dynamics of lipid molecules near the Ca2+-stimulated, Mg2e-dependent adenosinetriphosphatase (Ca2+-ATPase; ATP phosphohydrolase, EC 3.6.1.3) of sarcoplasmic reticulum. Measurements of the steady-state fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene in progressively delipidated sarcoplasmic reticulum membranes have been quantitatively interpreted in terms of a layer of lipid of high anisotropy (the lipid annulus) coexisting with lipid layers of very low anisotropy. In addition, the Ca2+-ATPase has been reconstituted into pure 1,2-dipentadecanoyl 3-sn-phosphatidylcholine membranes over a range of lipid-to-protein ratios. The effect of an intrinsic membrane protein on the molecular structure and dynamics of its surrounding lipid bilayer has been the subject of intense debate in recent years. Mainly on the basis of ESR and fluorescent probe studies, it is widely believed that proteins inserted into the membrane tend to restrict the motion of neighboring lipid molecules (see refs. 1 and 2 for reviews). These studies have suggested the coexistence of normal and motionally restricted bilayer domains within proteincontaining membranes (3-5). The restricted, protein-associated domain is frequently referred to as "annular" (5) or "boundary" (3) lipid. However, there is not universal agreement with this view. The major objection to this simple model has been that deuterium nuclear magnetic resonance (21H NMR) probes display a spectrum characteristic of a more disordered environment in protein-lipid recombinant membranes than in pure lipid bilayers (6,7). A possible resolution of the apparent disparity between ESR and 2H NMR has been suggested in terms of both the different time resolutions of these two techniques and a proposed disordered protein surface (6,8). Other objections to the boundary model have stressed protein aggregation as a possible source of "trapped" and therefore motionally inhibited lipid (9,10) or the fact that quantitative data analysis suggests the presence of more than just boundary and normal lipids in membranes containing intrinsic proteins (11)(12)(13) (14). MATERIALS AND METHODSMicrosomes containing the Mg2+-dependent, Ca2+-stimulated adenosinetriphosphatase (Ca2+-ATPase; ATP phosphohydrolase, EC 3.6.1.3) were isolated from rabbit white muscle and delipidated with sodium cholate as described (13), resulting in membranes containing endogenous phospholipid at various lipidto-protein ratios, and in which the protein content was 90% Ca2+-ATPase. These were used in our fluorometric studies. For calorimetric studies, such membrane preparations were further delipidated by precipitation with polyethylene glycol and remaining native lipids were replaced by synthetic 1,2-dipentadecanoyl 3-sn-phosphatidylcholine [(C15)2-PtdCho; Avanti Biochemicals] in the presence of sodium deoxycholate, using procedures similar to those previously described (15). The only modification was removal of solubilizing dete...

show abstract

“…The recombinant systems with cytochrome oxidase and dimyristoylglycerophosphocholine were prepared essentially as described by Gomez-Fernandez et al [23]. The fluorescence polarization measurements were performed using an Elscint Microviscosimeter MVla.…”

Section: Methodsmentioning

confidence: 99%

Intrinsic Molecules in Fluid Phospholipid Bilayers. Fluorescence Probe Studies

et al. 1981

Self Cite

View full text Add to dashboard Cite

Fluorescence probe data using 1,6-diphenyl-I ,3,5-hexatriene for various concentrations of intrinsic molecules (cholesterol, gramicidin A and cytochrome oxidase) within fluid lipid bilayers have been examined. The polarization value increases with increasing concentration of intrinsic molecule and then approaches a limiting value. Empirical curve-fitting of the experimental data, change of polarization with concentration, shows that each system can be fitted approximately by an exponential curve.A theory has been constructed based upon the assumption that only one intrinsic molecule need be adjacent to a fluorescent probe molecule to affect its motion drastically. The change in probe motion then depends upon the probability p of all positions next to a lipid chain being free of intrinsic molecules. The value of the probability p has been calculated and it is shown that p = (1 -x ) " where x = c or x = __ ~ depending on whether the intrinsic molecule spans the lipid bilayer or not. The approximation p = ePMx gives a good fit to the data for all x, thereby explaining the observed phenomenological fit.The fluorescent probe data is interpreted to show that protein-protein contacts increase as the intrinsic protein concentration increases within the lipid bilayer.An apparent dichotomy between the results from the fluorescence probe and from the deuterium magnetic resonance is explained in terms of a dominant affect on the probe being its hindrance to motion by interaction with the intrinsic molecule (protein) whilst individual C2Hz groups of the chain may exhibit greater disorder.The studies of protein-lipid interactions and cholesterollipid interactions are important for achieving a good basic understanding of biomembrane structure and function. The way in which the fluidity of the lipid bilayer matrix can be modulated by intrinsic molecules has been studied by variety of physical techniques including calorimetry and spectroscopic methods [l]. Some of these techniques involve the use of probe molecules and fluorescent probes have been developed for this purpose. Essentially, the probe molecule is considered to mimic a lipid molecular or lipid chain and then deductions are made concerning, for example, the change of lipid fluidity as the intrinsic protein (or cholesterol) concentration is increased. Some workers have interpreted probe data, particularly spin-probe studies of protein-lipid systems in terms of long-lived protein-lipid complexes where the lipid in the boundary region is rigid or ordered [2,3]. Recent deuterium magnetic resonance studies indicate that the intrinsic proteins (as distinct from cholesterol) disorder the lipid chains rather than increase their order and that rapid exchange of all lipids occurs [4,5]. There appears to be a dichotomy between the results obtained by some workers using spin-label data and the studies of deuterium magnetic resonance.In the present paper we discuss our studies of intrinsic molecules (cholesterol, gramicidin A and proteins) in fluid bilayers using the fluorescent p...

show abstract

Protein-lipid interaction

Cited by 102 publications

References 32 publications

On the interaction of ubiquinones with phospholipid bilayers

On the interaction of ubiquinones with phospholipid bilayers

Ordered and disordered phospholipid domains coexist in membranes containing the calcium pump protein of sarcoplasmic reticulum.

Intrinsic Molecules in Fluid Phospholipid Bilayers. Fluorescence Probe Studies

Contact Info

Product

Resources

About