geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Interaction of lipopolysaccharide and phospholipid in mixed membranes: solid-state 31P-NMR spectroscopic and microscopic investigations


, : Interaction of lipopolysaccharide and phospholipid in mixed membranes: solid-state 31P-NMR spectroscopic and microscopic investigations. Biophysical Journal 95(3): 1226-1238

Lipopolysaccharide (LPS), which constitutes the outermost layer of gram-negative bacterial cells as a typical component essential for their life, induces the first line defense system of innate immunity of higher animals. To understand the basic mode of interaction between bacterial LPS and phospholipid cell membranes, distribution patterns were studied by various physical methods of deep rough mutant LPS (ReLPS) of Escherichia coli incorporated in phospholipid bilayers as simple models of cell membranes. Solid-state (31)P-NMR spectroscopic analysis suggested that a substantial part of ReLPS is incorporated into 1,2-dimyristoyl-sn-glycero-3-phosphocholine lipid bilayers when multilamellar vesicles were prepared from mixtures of these. In egg L-alpha-phosphatidylcholine (egg-PC)-rich membranes, ReLPS undergoes micellization. In phosphatidylethanolamine-rich membranes, however, micellization was not observed. We studied by microscopic techniques the location of ReLPS in membranes of ReLPS/egg-PC (1:10 M/M) and ReLPS/egg-PC/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol (POPG) (1:9:1 M/M/M). The influence of ReLPS on the physicochemical properties of the membranes was studied as well. Microscopic images of both giant unilamellar vesicles and supported planar lipid bilayers showed that LPS was uniformly incorporated in the egg-PC lipid bilayers. In the egg-PC/POPG (9:1 M/M) lipid bilayers, however, ReLPS is only partially incorporated and becomes a part of the membrane in a form of aggregates (or as mixed aggregates with the lipids) on the bilayer surface. The lipid lateral diffusion coefficient measurements at various molar ratios of ReLPS/egg-PC/POPG indicated that the incorporated ReLPS reduces the diffusion coefficients of the phospholipids in the membrane. The retardation of diffusion became more significant with increasing POPG concentrations in the membrane at high ReLPS/phospholipid ratios. This work demonstrated that the phospholipid composition has critical influence on the distribution of added ReLPS in the respective lipid membranes and also on the morphology and physicochemical property of the resulting membranes. A putative major factor causing these phenomena is reasoned to be the miscibility between ReLPS and individual phospholipid compositions.

US$19.90

PMID: 18456825

DOI: 10.1529/biophysj.108.131706


Other references

Doly, M.; Oustrin, J., 1996: Suppression of platelet activating factor effects on the retina by inhibitors of G-proteins. The Platelet Activating Factor (PAF) have been shown to alter the transretinal potential recorded from light stimulated isolated retina. In the present study, we investigated the effect of cholera and pertussis toxins on PAF-induced electroretinog...

Sato, G.I.hi; Shin Ei, Y.; Nishimoto, K., 1954: Experience of insulin subshock therapy. Insulin subshock therapy plays an important role in psychotherapy as a "side treatment" of neuroses. The usual procedure is to begin with 5-10 units of insulin, increasing the dose daily until symptoms of hypo- glycemia are produced. Fol...

Barrell, M., 2001: Midwives need to make a difference. Practising Midwife 3(6): 4-5

Evans H.H.; Ramakrishnan N.; Clay M.E.; Antunez A.R.; Oleinick N.L., 1988: Dna degradation induced by photodynamic treatment parallels cytotoxicity in l5178y cells. Journal of Cell Biology 107(6 PART 3): 519A

Braha, D.; Bar-Yam, Y., 2004: Topology of large-scale engineering problem-solving networks. The last few years have led to a series of discoveries that uncovered statistical properties that are common to a variety of diverse real-world social, information, biological, and technological networks. The goal of the present paper is to invest...

Campiglio, A., 1969: Microdetermination of carbon and hydrogen in organic compounds with volumetric final determination. Il Farmaco; Edizione Scientifica 24(9): 800-823

Haraguchi, T.; Oguro, M.; Nagano, H.; Ichihara, A.; Sakamura, S., 1983: Specific inhibitors of eukaryotic DNA synthesis and DNA polymerase alpha, 3-deoxyaphidicolin and aphidicolin-17-monoacetate. Of several phytotoxins isolated from culture filtrates of Phoma betae Frank PS-13, an incitant of leaf spot disease of sugar beet, three have been identified as aphidicolin, 3-deoxyaphidicolin and aphidicolin-17-monoacetate. Aphidicolin is a selec...

Kuno, T.; Nagura, Y.; Takahashi, S., 1994: Biofiltration. Japanese Journal of Artificial Organs 23(6): 1156-1164

Hafner, M.Botta.; Zanatta, J.; Rasera Zotelli, V.Lucia.; Batista, Mília.Jesus.; Sousa, M.da.Luz.Rosário., 2014: Perception of toothache in adults from state capitals and interior cities within the Brazilian geographic regions. Studies emphasizing toothache in adulthood are scarce in Brazil. A greater understanding of both the prevalence and the self-perception of pain among individuals in this age group (35 to 44 years old) is important, especially considering that this...

Sesen, H.; Basim, N.H., 2012: Impact of satisfaction and commitment on teachers’ organizational citizenship. This study examined the impact of job satisfaction and organizational commitment on teachers organizational citizenship behavior (OCB) in a structural equation model. The study was employed to a group of teachers and their supervisors. The results...