Evidence of bilayer structure and of membrane interactions from X-ray diffraction analysis

Blaurock, A.E.

doi:10.1016/0304-4157(82)90016-8

Cited by 134 publications

(67 citation statements)

References 95 publications

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“…1 B. The orientational behaviour of the foils used for the Xray experiments was analogous to that previously observed for hpopolysdccharides and lipid-A foils [4]. From the observation of a series of equatorially oriented scattering maxima, all of which corresponded to different diffraction orders caused by a single periodicity [22] Comparison of the scattering behaviour of lipid A from S. minnesota and its synthetic hepta-acyl counterpart 516 revealed strong distinctions between both samples (Fig. 1 E, F).…”

Section: X-ray Datamentioning

confidence: 54%

“…The corresponding value of 4.2 nm for sample 302 was somewhat higher, so that a bilayered structure cannot be excluded with the same confidence. However, because of the overall similarity in the X-ray pattern of compounds 316 and 302 and because of the non-existence of further diffuse bands corresponding to 4.212 nm or 4.213 nm [22] we consider the of compounds 506 and 516 were found to be considerably smaller than those detected for the natural products. Fig.…”

Section: Long Runge Ordermentioning

confidence: 96%

“…[22], nor of an ordered hexagonal arrangement (/I-phase according to [23]) of the fatty acyl chains for which a sharp reflection at about 0.42 nm would be characteristic [23].…”

Section: X-ray Datamentioning

confidence: 99%

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Comparative X‐ray and Fourier‐transform‐infrared investigations of conformational properties of bacterial and synthetic lipid A of Escherichia coli and Salmonella minnesota as well as partial structures and analogues thereof

Labischinski

Naumann

Schultz

et al. 1989

European Journal of Biochemistry

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By using the X-ray and infrared spectroscopic characteristics of various synthetic analogues and partial structures of lipid A in the dried state, a comparison of these compounds with their natural counterparts was undertaken. As judged by their X-ray diffraction and infrared spectroscopic features, the compounds tested could be divided into two main groups. The first group covered those samples synthesized in accordance with a previously assumed structure, while those synthesized in accordance with present knowledge on the lipid-A primary structure formed the second group. Members of the first group were characterized by a liquid-like, atype arrangement of their fatty acyl chains in a non-lamellar supramolecular structure, while all members of the second group formed bilayered phases with a much more ordered, p-type conformation of their fatty acyl chains. Synthetic Escherichia coli-type lipid A (compound 506), proved to be essentially identical to its natural counterpart with respect to those conformational properties accessible by our methods. The synthetic hepta-acyl species of Salmonella minnesota lipid A (compound 516) revealed an unexpected conformational behaviour, whereby a fattyacyl-chain packing could be detected which was different from the hexagonal arrangement found for all other compounds of the second group.The pathophysiological activities of lipopolysaccharides (endotoxins) of gram-negative bacteria in mammals, including lethal toxicity, pyrogenicity, immunomodulating and antitumor activities, are dependent on their lipid-A component [I]. The conformational rigidity of lipopolysaccharide and lipid A also seems to play an important role for the well known permeation-barrier properties of the outer membrane of gram-negative organisms [2 -51.Compared to other membrane-forming lipids, lipid A exhibits a considerable chemical complexity in consisting of a (p 1 -6)-linked D-glucosamine disaccharide substituted by phosphoryl groups, ester-and amide-linked (R)-3-hydroxy fatty acids, which may, in turn, carry other fatty acids at their 3-hydroxyl groups. Furthermore, although the primary structure of the lipid-A component in many bacteria appears to be quite similar, several minor variations exist [6], and even in samples isolated from a single strain of bacteria an intrinsic chemical heterogeneity has been observed [7, 81. It was, therefore, found to be extremely difficult to unequivocally elucidate its detailed chemical structure and those entities of the molecule responsible and/or necessary for the expression of the various biological properties of lipid A.In order to overcome these problems lipid A, lipid-A partial structures and analogues of lipid A have been chemically synthesized and biologically analysed [9-141. It was shown

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Section: X-ray Datamentioning

confidence: 54%

Section: Long Runge Ordermentioning

confidence: 96%

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Comparative X‐ray and Fourier‐transform‐infrared investigations of conformational properties of bacterial and synthetic lipid A of Escherichia coli and Salmonella minnesota as well as partial structures and analogues thereof

Labischinski

Naumann

Schultz

et al. 1989

European Journal of Biochemistry

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“…An alternative approach, using low-angle x-ray diffraction analysis, was taken. This was used to measure the interbilayer spacing of isolated membrane lipids which were believed to be in a multilamellar arrangement (4,9). The interbilayer spacing depends on bilayer thickness, which in turn depends on the phase of the lipid acyl chains.…”

Section: Changes In Lipid Phase Transition Temperature During Flowermentioning

confidence: 99%

Changes in the Physical State of Membrane Lipids during Senescence of Rose Petals

Faragher

Wachtel²,

Mayak³

1987

Plant Physiol.

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Changes in the physical state of microsomal membrane lipids during senescence of rose flower petals (Rosa hyb. L. cv Mercedes) were measured by x-ray diffraction analysis. During senescence of cut flowers held at 22°C, lipid in the ordered, gel phase appeared in the otherwise disordered, liquid-crystalline phase lipids of the membranes. This was due to an increase in the phase transition temperature of the lipids. The proportion of gel phase in the membrane lipids of 2-day-old flowers was estimated as about 20% at 22°C. Ethylene may be responsible, at least in part, for the increase in lipid transition temperature during senescence since aminooxyacetic acid and silver thiosulfate inhibited the rise in transition temperature. When flowers were stored at 3°C for 10 to 17 days and then transferrd to 22°C, gel phase lipid appeared in membranes earlier than in freshly cut flowers. This advanced senescence was the result of aging at 3°C, indicated by increases in membrane lipid transition temperature and ethylene production rate during the time at 3°C. It is concluded that changes in the physical state of membrane lipids are an integral part of senescence of rose petals, that they are caused, at least in part, by ethylene action and that they are responsible, at least in part, for the increase in membrane permeability which precedes flower death.cence processes have not been investigated. For example, it is not known whether the membrane changes precede, or are a result of, the increase in ethylene production. It is known that ethylene increases membrane permeability in rose petals (10) and that changes in the physical state of membrane lipids can increase membrane permeability (2,8). Therefore, it is reasonable to propose that ethylene may alter the physical properties of rose petal membranes and hence increase their permeability.In the work reported here we investigated changes in the physical state of microsomal membrane lipids during senescence of rose petals. The physical state of lipids was measured by a direct method, x-ray diffraction analysis, which reveals the phase properties and ordering of the lipid acyl chains ( 14). The changes in the membrane lipids have been related to other senescence processes (ethylene production and membrane permeability) during senescence, and after treatments which hastened or slowed senescence. In particular, the possible role of ethylene in regulating changes in membrane lipids was investigated. MATERIALS AND METHODSSenescence of rose petals involves a climacteric-like rise in ethylene production followed by increased membrane permeability to electrolytes, petal wilting, and death (10). Ethylene action is, at least in part, responsible for the increased membrane permeability which presumably leads to death (10,20). During plant senescence critical changes occur in the physical state of membrane lipids which alter the functional integrity of membranes and lead to cell death (7,16,22 Flowers and Treatments. Flowers of the rose (Rosa hyb L.) cv Mercedes were grown, cut, a...

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“…For a multilamellar lipid stack the relative vertical electron density prole ∆ρ(z) can be reconstructed from the integrated Bragg peak intensities I(0, q z (n)) and the corresponding positions q z (n) as obtained from a standard reectivity measurement by the well known Fourier synthesis approach [94,95].…”

Section: Specular Scattering From Lipid Multilayersmentioning

confidence: 99%

Non-equilibrium dynamics of lipid bilayers

Reusch¹

2013

Göttingen Series in X-Ray Physics

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Evidence of bilayer structure and of membrane interactions from X-ray diffraction analysis

Cited by 134 publications

References 95 publications

Comparative X‐ray and Fourier‐transform‐infrared investigations of conformational properties of bacterial and synthetic lipid A of Escherichia coli and Salmonella minnesota as well as partial structures and analogues thereof

Comparative X‐ray and Fourier‐transform‐infrared investigations of conformational properties of bacterial and synthetic lipid A of Escherichia coli and Salmonella minnesota as well as partial structures and analogues thereof

Changes in the Physical State of Membrane Lipids during Senescence of Rose Petals

Non-equilibrium dynamics of lipid bilayers

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