The specific interaction of myelin basic protein with lipids at the air-water interface

Demel, R.A.; London, Y.; Kessel, W.S.M. Geurtz van; Vossenberg, F.G.A.; Deenen, L.L.M. Van

doi:10.1016/0005-2736(73)90126-0

Cited by 209 publications

(86 citation statements)

References 25 publications

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“…Proteins that only interact with the lipid head groups without actually inserting between the lipid molecules, do not induce an increase in the surface pressure. 16 The monolayer experiments were performed with lipid monolayers composed of DOPC/ DOPS in a 7:3 molar ratio. This composition was chosen because these phospholipids represent the most abundant zwitterionic phospholipid species (PC) and the dominant negatively charged phospholipid species (PS) in eukaryotic cells.…”

Section: Resultsmentioning

confidence: 99%

“…To test this, we studied the insertion behaviour of two hIAPP fragments. The first fragment is a peptide composed of the first 19 amino acid residues of hIAPP (hIAPP [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] ), which is nearly identical with the N-terminal part of mIAPP. The second fragment, hIAPP [20][21][22][23][24][25][26][27][28][29] , is composed of amino acid residues 20 to 29 of hIAPP, and is able to form amyloid fibrils in vitro but lacks the N-terminal part.…”

Section: The N-terminal Part Of Hiapp Is Responsible For Insertion Inmentioning

confidence: 99%

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Islet Amyloid Polypeptide Inserts into Phospholipid Monolayers as Monomer

Engel

Yigittop

Elgersma

et al. 2006

Journal of Molecular Biology

168

186

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Amyloid deposits in the pancreatic islets of Langerhans are thought to be a main factor responsible for death of the insulin-producing islet b-cells in type 2 diabetes. It is hypothesized that b-cell death is related to interaction of the 37 amino acid residue human islet amyloid polypeptide (hIAPP), the major constituent of islet amyloid, with cellular membranes. However, the mechanism of hIAPP-membrane interactions is largely unknown. Here, we study the nature and the molecular details of the initial step of hIAPPmembrane interactions by using the monolayer technique. It is shown that both freshly dissolved hIAPP and the non-amyloidogenic mouse IAPP (mIAPP) have a pronounced ability to insert into phospholipid monolayers, even at lipid packing conditions that exceed the conditions that occur in biological membranes. In contrast, the fibrillar form of hIAPP has lost the ability to insert. These results, combined with the observations that both the insertion kinetics and the dependence of insertion on the initial surface pressure are similar for freshly dissolved hIAPP and mIAPP, indicate that hIAPP inserts into phospholipid monolayers most likely as a monomer. In addition, our results suggest that the N-terminal part of hIAPP, which is nearly identical with that of mIAPP, is largely responsible for insertion. This is supported by experiments with hIAPP fragments, which show that a peptide consisting of the 19 N-terminal residues of hIAPP efficiently inserts into phospholipid monolayers, whereas an amyloidogenic decapeptide, consisting of residues 20-29 of hIAPP, inserts much less efficiently. The results obtained here suggest that hIAPP monomers might insert with high efficiency in biological membranes in vivo. This process could play an important role as a first step in hIAPP-induced membrane damage in type 2 diabetes.

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Section: Resultsmentioning

confidence: 99%

Section: The N-terminal Part Of Hiapp Is Responsible For Insertion Inmentioning

confidence: 99%

Islet Amyloid Polypeptide Inserts into Phospholipid Monolayers as Monomer

Engel

Yigittop

Elgersma

et al. 2006

Journal of Molecular Biology

168

186

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“…No evidence is, at present, available which suggests that lysozyme acts as an enzyme on any nonbacterial substrate, although interactions with cartilage (36) and cell membranes (37,38) may be due to its unique polyelectrolyte properties. Even its role in extracellular killing of microorganisms is not fully understood, although the range of susceptible organisms could be expanded by synergistic action between lysozyme, antibody, and complement (39,40).…”

Section: Discussionmentioning

confidence: 99%

In Vitro Synthesis and Secretion of Lysozyme by Mononuclear Phagocytes

Gordon

Todd

Cohn

1974

The Journal of Experimental Medicine

467

174

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In 1922 Alexander Fleming described the remarkable bacteriolytic activity of an enzyme, lysozyme, which was widely distributed in tissues and secretions (1). Lysozyme (muramidase) is a cationic enzyme, tool wt 14,307, which hydrolyses N-acetyl muramic /3-1, 4 N-acetyl glucosamine linkages in the bacterial cell wall (2). Although a great deal is known about its structure and enzymology its function other than in host defence is still poorly understood.High concentrations of lysozyme are found in leukocytes, especially the polymorphonuclear leukocyte (PMN) 1 and rabbit alveolar macrophage (3). Fractionation studies of the rabbit P M N show that 70 % of its intracellular lysozyme is sedimentable and, unlike other hydrolases, it is found in both the azurophil and specific granules of the cell (4). The BCG-induced rabbit alveolar macrophage is able to release a large fraction of its intracellular lysozyme into the medium during phagocytosis (5) and may secrete lysozyme during cultivation in vitro (6). Large amounts of lysozyme accumulate in the serum and urine of patients (7) and animals (8) bearing monocytic leukemia.In this paper we report that mouse peritoneal macrophages and human monocytes synthesize and secrete substantial amounts of lysozyme in culture. We also study factors which influence the rate of lysozyme production and examine the effect of phagocytosis on its secretion. Materials and MethodsCell C u l t u r e s . -Mouse peritoneal macrophages: Female mice of the NCS (Rockefeller) strain, weighing 25-30 g were used. Peritoneal macrophages were harvested, without anticoagulants, by standard procedures (9); the cells were obtained either 4 days after stimulation by intraperitoneai injection of 0.75 ml thioglycollate medium (I0) or from control, unstimulated mice. The cell yield from unstimulated mice was 5-8 X 106 cells, of which 30-40% were macrophages and the remainder lymphocytes; thioglycollate-stimulated mice yielded 15-20 X 106 cells, consisting of 75-90% macrophages and 10-25% lymphocytes.

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“…Further detailed studies indicate that the N-terminal region of the basic protein (residues 20-113) interacts in a different manner compared with the rest of the protein molecule (Gould & London, 1972;Demel et al, 1973;. The interaction of the basic protein with lipids has been reviewed by Rumsby & Crang (1977) in relation to the molecular architecture of the myelin sheath.…”

mentioning

confidence: 99%

Localization of sites for ionic interaction with lipid in the C-terminal third of the bovine myelin basic protein

Jones¹,

Rumsby²

1977

Biochemical Journal

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The myelin basic protein from bovine brain tissue was purified and the two peptides obtained by cleavage of the polypeptide chain at the single tryptophan residue were isolated. The interaction of these peptides and the intact basic protein with complex lipids was investigated by following the solubilization of lipid-protein complexes into chloroform in a biphasic solvent system. The C-terminal peptide fragment (residues 117-170) and the intact basic protein both formed chloroform-soluble complexes with acidic lipids, but not with neutral complex lipids. The N-terminal fragment (residues 1-115) did not form chloroform-soluble complexes with either acidic or neutral complex lipids. The molar ratio of lipid to protein that caused a 50 % loss of protein from the upper phase to the lower chloroform phase was the same for the intact basic protein as for the smaller C-terminal peptide fragment. Phosphatidylserine and phosphatidylinositol were approximately twice as efficient as sulphatide at causing protein redistribution to the chloroform phase. The results are interpreted as indicating that the sites for ionic interactions between lipid and charged groups on the basic protein of myelin are located in the C-terminal region of the protein molecule.

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The specific interaction of myelin basic protein with lipids at the air-water interface

Cited by 209 publications

References 25 publications

Islet Amyloid Polypeptide Inserts into Phospholipid Monolayers as Monomer

Islet Amyloid Polypeptide Inserts into Phospholipid Monolayers as Monomer

In Vitro Synthesis and Secretion of Lysozyme by Mononuclear Phagocytes

Localization of sites for ionic interaction with lipid in the C-terminal third of the bovine myelin basic protein

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