Oxygen Binding Properties and Tetrameric Stability of Hemoglobins From the Snakes Crotalus Durissus Terrificus and Liophis Miliaris

Secretory phospholipases A2(sPLA2) exert proinflammatory actions through lipid mediators. These enzymes have been found to be elevated in many inflammatory disorders such as rheumatoid arthritis, sepsis, and atherosclerosis. The aim of this study was to evaluate the effect of harpalycin 2 (Har2), an isoflavone isolated fromHarpalyce brasilianaBenth., in the enzymatic, edematogenic, and myotoxic activities of sPLA2fromBothrops pirajai, Crotalus durissus terrificus, Apis mellifera,andNaja najavenoms. Har2 inhibits all sPLA2tested. PrTX-III (B. pirajaivenom) was inhibited at about 58.7%, Cdt F15 (C. d. terrificusvenom) at 78.8%, Apis (from bee venom) at 87.7%, and Naja (N. najavenom) at 88.1%. Edema induced by exogenous sPLA2administration performed in mice paws showed significant inhibition by Har2 at the initial step. In addition, Har2 also inhibited the myotoxic activity of these sPLA2s. In order to understand how Har2 interacts with these enzymes, docking calculations were made, indicating that the residues His48 and Asp49 in the active site of these enzymes interacted powerfully with Har2 through hydrogen bonds. These data pointed to a possible anti-inflammatory activity of Har2 through sPLA2inhibition.

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Thermolability of 28S ribosomal ribonucleic acid from the liver of Crotalus durissus terrificus (Ophidia, Reptilia)

Biochemical Journal ◽

10.1042/bj1350073 ◽

1973 ◽

Vol 135 (1) ◽

pp. 73-79 ◽

Cited By ~ 8

Author(s):

J. F. Giorgini ◽

F. L. De Lucca

Keyword(s):

Molecular Weight ◽

Gradient Centrifugation ◽

Polyacrylamide Gel Electrophoresis ◽

Sucrose Density Gradient ◽

Dimethyl Sulphoxide ◽

Low Molecular Weight ◽

28S Rrna ◽

Sucrose Density Gradient Centrifugation ◽

Crotalus Durissus Terrificus ◽

Crotalus Durissus

Instability of 28S rRNA of Crotalus durissus terrificus liver was observed during hotphenol extraction: purified 28S rRNA is converted into an 18S RNA component by heat treatment. It was also found that ‘6S’ and ‘8S’ low-molecular-weight RNA species were released during the thermal conversion. This conversion and the release of the low-molecular-weight species were also induced by 8m-urea and 80% (v/v) dimethyl sulphoxide at 0°C. Evidence is presented that this phenomenon is an irreversible process and results from the rupture of hydrogen bonds. The 18S RNA product was shown to be homogeneous by polyacrylamide-gel electrophoresis and by sucrose-density-gradient centrifugation. The base composition of the 18S RNA products obtained by heat, urea or dimethyl sulphoxide treatments was similar. The C+G content of the 18S RNA product was different from that of the native 18S rRNA, but similar to that of 28S rRNA.

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Effects of temperature on lung and blood gases in the South American rattlesnake Crotalus durissus terrificus

Comparative Biochemistry and Physiology Part A Molecular & Integrative Physiology ◽

10.1016/s1095-6433(98)10102-2 ◽

1998 ◽

Vol 121 (1) ◽

pp. 7-11 ◽

Cited By ~ 23

Author(s):

Tobias Wang ◽

Augusto S. Abe ◽

Mogens L. Glass

Keyword(s):

Blood Gases ◽

South American ◽

The South ◽

Crotalus Durissus Terrificus ◽

Effects Of Temperature ◽

Crotalus Durissus

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Haemoglobin polymorphisms affect the oxygen-binding properties in Atlantic cod populations

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2008.1529 ◽

2008 ◽

Vol 276 (1658) ◽

pp. 833-841 ◽

Cited By ~ 62

Author(s):

Øivind Andersen ◽

Ola Frang Wetten ◽

Maria Cristina De Rosa ◽

Carl Andre ◽

Cristiana Carelli Alinovi ◽

...

Keyword(s):

Evolutionary Biology ◽

Quaternary Structure ◽

Atlantic Cod ◽

Three Dimensional ◽

Oxygen Affinity ◽

Oxygen Binding ◽

Low Oxygen ◽

Binding Properties ◽

Important Species ◽

The North

A major challenge in evolutionary biology is to identify the genes underlying adaptation. The oxygen-transporting haemoglobins directly link external conditions with metabolic needs and therefore represent a unique system for studying environmental effects on molecular evolution. We have discovered two haemoglobin polymorphisms in Atlantic cod populations inhabiting varying temperature and oxygen regimes in the North Atlantic. Three-dimensional modelling of the tetrameric haemoglobin structure demonstrated that the two amino acid replacements Met55β 1 Val and Lys62β 1 Ala are located at crucial positions of the α 1 β 1 subunit interface and haem pocket, respectively. The replacements are proposed to affect the oxygen-binding properties by modifying the haemoglobin quaternary structure and electrostatic feature. Intriguingly, the same molecular mechanism for facilitating oxygen binding is found in avian species adapted to high altitudes, illustrating convergent evolution in water- and air-breathing vertebrates to reduction in environmental oxygen availability. Cod populations inhabiting the cold Arctic waters and the low-oxygen Baltic Sea seem well adapted to these conditions by possessing the high oxygen affinity Val55–Ala62 haplotype, while the temperature-insensitive Met55–Lys62 haplotype predominates in the southern populations. The distinct distributions of the functionally different haemoglobin variants indicate that the present biogeography of this ecologically and economically important species might be seriously affected by global warming.

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