Structural characterization of naturally occurring RNA single mismatches

Naturally occurring 2-hydroxy-1,4-naphthoquinones are well known to form readily stable complexes with transition metals. In this short communication we describe for the first time the synthesis and preliminary data about structural characterization of complexes between two naturally widespread 2-hydroxy-1,4-naphthoquinones, namely lapachol (1) and lawsone (2), with selected lanthanides like lanthanum, gadolinium, and ytterbium. When tested as cytotoxic compounds, such complexes exhibited an activity that was either higher or equal to that of the parent naphthoquinone.

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The X-ray structure of human P-cadherin EC1-EC2 in a closed conformation provides insight into the type I cadherin dimerization pathway

Acta Crystallographica Section F Structural Biology Communications ◽

10.1107/s2053230x15003878 ◽

2015 ◽

Vol 71 (4) ◽

pp. 371-380 ◽

Cited By ~ 6

Author(s):

Andrea Dalle Vedove ◽

Anna Paola Lucarelli ◽

Valentina Nardone ◽

Angelica Matino ◽

Emilio Parisini

Keyword(s):

Structural Characterization ◽

Adherens Junction ◽

Large Family ◽

Type I ◽

Calcium Dependent ◽

Closed Conformation ◽

Naturally Occurring ◽

Packing Arrangement

Cadherins are a large family of calcium-dependent proteins that mediate cellular adherens junction formation and tissue morphogenesis. To date, the most studied cadherins are those classified as classical, which are further divided into type I or type II depending on selected sequence features. Unlike other members of the classical cadherin family, a detailed structural characterization of P-cadherin has not yet been fully obtained. Here, the high-resolution crystal structure determination of the closed form of human P-cadherin EC1-EC2 is reported. The structure shows a novel, monomeric packing arrangement that provides a further snapshot in the yet-to-be-achieved complete description of the highly dynamic cadherin dimerization pathway. Moreover, this is the first multidomain cadherin fragment to be crystallized and structurally characterized in its closed conformation that does not carry any extra N-terminal residues before the naturally occurring aspartic acid at position 1. Finally, two clear alternate conformations are observed for the critical Trp2 residue, suggestive of a transient, metastable state. The P-cadherin structure and packing arrangement shown here provide new and valuable information towards the complete structural characterization of the still largely elusive cadherin dimerization pathway.

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Composition of Color Substances of Hevea Brasiliensis Natural Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3539403 ◽

2007 ◽

Vol 80 (2) ◽

pp. 212-230 ◽

Cited By ~ 4

Author(s):

Jitladda Sakdapipanich ◽

Kittipong Insom ◽

Nataphon Phupewkeaw

Keyword(s):

Fatty Acids ◽

High Resolution ◽

Natural Rubber ◽

Structural Characterization ◽

Unsaturated Fatty Acids ◽

Rubber Latex ◽

Naturally Occurring ◽

Bottom Fraction ◽

Light Color

Abstract It is accepted that NR gives naturally occurring color, which restrict many applications such as light-color products. Therefore, characterization of color substances presenting in NR is very useful to develop the certain methodology to eliminate them completely or partly from NR in the future. In this work, an attempt was made to purify and characterize the color substances extracted from various fractions of Hevea rubber latex by certain methods, using high-resolution structural characterization techniques. It was found that the content of color substances extracted from fresh latex (FL), rubber cream, bottom fraction (BF), Frey Wyssling (FW) particles and STR 20 were different. Based on the high-resolution spectroscopic analyzes, it was found that the color substances extracted from NR were composed of carotenoids, tocotrienol esters, fatty alcohol esters, tocotrienols, unsaturated fatty acids, fatty alcohols, diglyceride and monoglyceride. The results will be useful for rubber-technologist to identify the origin to make obnoxious color in natural rubber, especially in some applications which are restricted by such the color.

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Biosynthesis, isolation, and structural characterization of ε-poly-l-lysine produced by Streptomyces sp. DES20

RSC Advances ◽

10.1039/c6ra10829f ◽

2016 ◽

Vol 6 (63) ◽

pp. 58521-58528 ◽

Cited By ~ 4

Author(s):

Hongliu Gao ◽

Shi-Zhong Luo

Keyword(s):

Structural Characterization ◽

Antimicrobial Activities ◽

Streptomyces Sp ◽

Naturally Occurring

ε-Poly-l-lysine (ε-PL) is an unusual, naturally occurring homo-polyamide made of 25–35l-lysines with antimicrobial activities.

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Identification and Structural Characterization of Naturally-Occurring Broad-Spectrum Cyclic Antibiotics Isolated from Paenibacillus

Journal of the American Society for Mass Spectrometry ◽

10.1007/s13361-015-1190-2 ◽

2015 ◽

Vol 26 (10) ◽

pp. 1768-1779 ◽

Cited By ~ 4

Author(s):

Ann M. Knolhoff ◽

Jie Zheng ◽

Melinda A. McFarland ◽

Yan Luo ◽

John H. Callahan ◽

...

Keyword(s):

Structural Characterization ◽

Broad Spectrum ◽

Naturally Occurring

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Structural characterization of naturally occurring pteridines by laser desorption Fourier transform mass spectrometry

Journal of Mass Spectrometry ◽

10.1002/jms.1190300613 ◽

1995 ◽

Vol 30 (6) ◽

pp. 872-884 ◽

Cited By ~ 2

Author(s):

Robert L. Hettich ◽

K. Bruce Jacobson

Keyword(s):

Mass Spectrometry ◽

Fourier Transform ◽

Structural Characterization ◽

Fourier Transform Mass Spectrometry ◽

Laser Desorption ◽

Naturally Occurring

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High Resolution Replication of Organoclay Surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055126 ◽

1982 ◽

Vol 40 ◽

pp. 576-577

Author(s):

W. W. Barker ◽

W. E. Rigsby ◽

V. J. Hurst ◽

W. J. Humphreys

Keyword(s):

Clay Mineral ◽

Organic Molecule ◽

Organic Molecules ◽

X Ray Diffraction ◽

Xrd Pattern ◽

X Ray ◽

Naturally Occurring ◽

Silicate Layers ◽

Mineral Identification

Experimental clay mineral-organic molecule complexes long have been known and some of them have been extensively studied by X-ray diffraction methods. The organic molecules are adsorbed onto the surfaces of the clay minerals, or intercalated between the silicate layers. Natural organo-clays also are widely recognized but generally have not been well characterized. Widely used techniques for clay mineral identification involve treatment of the sample with H2 O2 or other oxidant to destroy any associated organics. This generally simplifies and intensifies the XRD pattern of the clay residue, but helps little with the characterization of the original organoclay. Adequate techniques for the direct observation of synthetic and naturally occurring organoclays are yet to be developed.

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New ultrastructural findings about Borrelia burgdorferi by cryofixation, negative staining, thin sectioning and scanning techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160467 ◽

1990 ◽

Vol 48 (3) ◽

pp. 582-583

Author(s):

S. F. Hayes ◽

M. D. Corwin ◽

T. G. Schwan ◽

D. W. Dorward ◽

W. Burgdorfer

Keyword(s):

Lyme Disease ◽

Borrelia Burgdorferi ◽

Structural Characterization ◽

Negative Staining ◽

Low Speed ◽

Thin Sectioning ◽

Ultrastructural Findings

Characterization of Borrelia burgdorferi strains by means of negative staining EM has become an integral part of many studies related to the biology of the Lyme disease organism. However, relying solely upon negative staining to compare new isolates with prototype B31 or other borreliae is often unsatisfactory. To obtain more satisfactory results, we have relied upon a correlative approach encompassing a variety EM techniques, i.e., scanning for topographical features and cryotomy, negative staining and thin sectioning to provide a more complete structural characterization of B. burgdorferi.For characterization, isolates of B. burgdorferi were cultured in BSK II media from which they were removed by low speed centrifugation. The sedimented borrelia were carefully resuspended in stabilizing buffer so as to preserve their features for scanning and negative staining. Alternatively, others were prepared for conventional thin sectioning and for cryotomy using modified procedures. For thin sectioning, the fixative described by Ito, et al.

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