Further studies on the spreading of biomembranes at the air/water interface Structure, composition, enzymatic activities of human erythrocyte and sarcoplasmic reticulum membrane films

Pattus, Franc; Rothen, C.; Streit, Marcus; Zahler, Peter

doi:10.1016/0005-2736(81)90292-3

Cited by 38 publications

(23 citation statements)

References 22 publications

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“…Axolemmal membrane vesicles from AEF were spread at the aidwater interface as described by Verger and collaborators (Verger and Pattus, 1976;Pattus et al, 1978aPattus et al, , 1981. In brief, the vesicles (2 to 4 mg protein/ ml) were allowed to flow down (approximate rate 10 plimin) a 5 mm diameter wetted glass rod positioned at a 45" angle across the surface of a compartment (36 ml) of a specially designed thermostated teflon-coated trough, with multiple compartments, filled with 10 mM Tris-HC1 buffer in 100 mM NaCl, 20 mM CaCl,, at pH 7.4.…”

Section: Preparation Of Axolemma Monolayersmentioning

confidence: 99%

“…However, the surface behavior of only a few monolayers from natural membranes has been partially studied. These monolayers conserve a lipid-protein ratio similar to that in the natural membrane, several membrane enzymes retain their enzymatic activity in the film, and the viability of transport and ion channel proteins is fully or partially maintained (Pattus et al, 1978a(Pattus et al, , 1981Schurholz and Schindler, 199 1). Planar supported monolayers of membrane antigens were used to study cell recognition events in the immune system (McConnel et al, 1986;CarpCn et al, 1991).…”

Section: Introductionmentioning

confidence: 97%

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Surface behavior of axolemma monolayers: Physico‐chemical characterization and use as supported planar membranes for cultured Schwann cells

Calderón

Maggio

Neuberger

et al. 1993

J of Neuroscience Research

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The axolemma membrane forms a stable and reproducible monomolecular layer at the air-aqueous interface. The major lipids and proteins are present in this monolayer in molar ratios similar to the original membrane. Acetylcholinesterase and Na-K-ATPase activities are preserved in the monolayer to levels of 64% and 25%, respectively. The total lipid fraction forms a homogeneously mixed phase. The presence of proteins in the monolayer introduces surface inhomogeneties. Among other features, this is revealed by the presence of two values of lateral pressure at which the monolayer shows partial or total collapse: a broad partial collapse at surface pressures between 13 to 30 mN/m and a sharp collapse point at 46 mN/m. The average molecular areas, the broad collapse point, and the variation of the surface potential per molecule suggest the relocation of protein components at surface pressures between 13 to 30 mN/m. The behavior is consistent with the extrusion and exposure of proteins toward the aqueous medium that depends on the lateral pressure. Schwann cells grown on coverslips coated with axolemma monolayers at 13 mN/m (beginning of the broad collapse) and 34 mN/m (above the broad collapse) recognize the difference in the surface organization of axolemma caused by the lateral pressure which affects their proliferation, morphology, and spatial pattern of organization. Our results show for the first time that response of Schwann cells depends on the intermolecular organization of the axolemma surface with which they interact. These results suggest that the local expression of putative surface molecules of axolemma that may mediate membrane recognition and the signalling of morphological and proliferative changes can be modulated by long range supramolecular properties.

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Section: Preparation Of Axolemma Monolayersmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 97%

Surface behavior of axolemma monolayers: Physico‐chemical characterization and use as supported planar membranes for cultured Schwann cells

Calderón

Maggio

Neuberger

et al. 1993

J of Neuroscience Research

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“…AChE activity is not related to the spherical shape of the red cells alone, since hypotonic swelling of normal erythrocytes did not give similar results. The altered erythrocyte membrane is probably related to the physical state of the lipid environment [22] and a change in the membrane surface pressure [23]. Modulation of the enzyme is possible, not only by lipids but by proteins as well [61].…”

Section: Hereditary Spherocytosis (Hs)mentioning

confidence: 99%

“…In studies on the spreading of biomembranes at the air-water interface, Pattus et a1 [23] have shown that AChE activity appears to be dependent on the surface pressure of the surrounding bilayer. In addition, drugs have been shown to inhibit the activity of membrane-bound AChE.…”

mentioning

confidence: 98%

Acetylcholinesterase in red blood cells

Lawson

Barr

1987

American J Hematol

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“…The mixture was subjected to three cycles of freezing and thawing. 10 l of this proteoliposome solution were added to 200 l of the recording solution, leading to the formation at the surface of the bath of a monolayer having the same composition in phospholipids and proteins as the proteoliposomes (52). Bilayers were formed by apposition at the tip of microelectrodes using the tip-dip technique (25).…”

Section: The Isolated Tom Complex Is Free Of Porin-omvsmentioning

confidence: 99%

The Isolated Complex of the Translocase of the Outer Membrane of Mitochondria

Künkele

Juin

Pompa

et al. 1998

Journal of Biological Chemistry

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The complex of the translocase mitochondrial outer membrane (TOM), mediates recognition, unfolding, and translocation of preproteins. We have used a combination of biochemical and electrophysiological methods to study the properties of the preprotein-conducting pore of the purified TOM complex. The pore is cation-selective and voltage-gated. It shows three main conductance levels with characteristic slow and fast kinetics transitions to states of lower conductance following application of transmembrane voltages. These electrical properties distinguish it from the mitochondrial voltagedependent anion channel (porin) and are identical to those of the previously described peptide-sensitive channel. Binding of antibodies to the C terminus of Tom40 on the intermembrane space side of the outer membrane modifies the channel properties and allows determination of the orientation of the channel within the lipid bilayer. Mitochondrial presequence peptides specifically interact with the pore and decrease the ion flow through the channel in a voltage-dependent manner. We propose that the presequence-induced closures of the pore are related to structural alterations of the TOM complex observed during the various stages of preprotein movement across the mitochondrial outer membrane.Translocation of preproteins across biological membranes involves proteinaceous machineries consisting of multiple components (for reviews, see Refs. 1-7). Some of these components are exposed to the cytosol and act as receptors by specifically deciphering the targeting information contained in the transported preproteins. Other proteins that are more embedded in the membrane also provide specific recognition sites for these targeting sequences and are responsible for the movement of the preproteins across the membrane, presumably by forming a preprotein-conducting hydrophilic pore. Only a few candidates for such aqueous channels have been described so far by electrophysiological methods (8 -11). Because entire membranes were used in those early studies, the connection between the observed channel activity and the preprotein translocation machinery could not be established with certainty. Recently, a purified component of the translocase of the chloroplast envelope membrane, termed Toc75, has been reported to form a voltage-gated ion-conducting pore, which appears to be involved in preprotein translocation (12).In mitochondria, translocation of preproteins is mediated by the translocases of the outer (TOM 1 complex) and inner (translocase of the inner membrane at mitochondria complexes) membranes. The TOM complex consists of protease-sensitive receptors that interact with preproteins during specific recognition of the cognate preproteins at the mitochondrial surface (e.g. see Refs. 13-16). Another set of TOM complex components is embedded in the outer membrane and is involved in the passage of the polypeptide chain into and across the membrane (17-19). These proteins provide a second presequence recognition site on the intermembrane space side of t...

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Further studies on the spreading of biomembranes at the air/water interface Structure, composition, enzymatic activities of human erythrocyte and sarcoplasmic reticulum membrane films

Cited by 38 publications

References 22 publications

Surface behavior of axolemma monolayers: Physico‐chemical characterization and use as supported planar membranes for cultured Schwann cells

Surface behavior of axolemma monolayers: Physico‐chemical characterization and use as supported planar membranes for cultured Schwann cells

Acetylcholinesterase in red blood cells

The Isolated Complex of the Translocase of the Outer Membrane of Mitochondria

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