THE PARTIAL AMINO ACID SEQUENCE OF LEAF-NOSED VIPER (ERISTICOPHIS MACMAHONII) SNAKE HEMOGLOBIN.
H. Waheed1, 2, S. K. Doman3 and A. Ahmed 3*
1H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi-75270, Pakistan; 2Dow University of Health Sciences, Karachi-74200, Pakistan
3Chapman University School of Pharmacy, Irvine, CA 92618, USA
Corresponding author Email: aahmed@chapman.edu
ABSTRACT
The hemoglobin from Leaf-nosed Viper (Eristocophis macmahonii) was analyzed to better understand interspecies relationship among various snakes at the molecular level. After isolation, the hemoglobin from erythrocytes was analyzed by cation-exchange chromatography. The chains from hemoglobin were separated by reversed phase-high performance liquid chromatography. The N-terminal amino acid sequences of globin chains were obtained by the process of Edman degradation in an automated protein sequencer using an online Phenylthiohydantoin (PTH) analyzer. The obtained sequences were compared using online pairwise sequence alignment tool and Clustal Omega. The N-terminal protein sequence results revealed that two hemoglobin components, comprised of αA, βI and βII -globin chains are expressed in Leaf-nosed viper. The αA-globin chain showed highest similarity with Sindhi krait, βI with Texas indigo snake and βII-with Indian cobra and interestingly with Blue-lipped sea krait (sea snake). N-terminal sequence alignment studies also showed some important amino acid substitutions that may affect iso-Hb composition and function.
Keywords: Eristocophis macmahonii; hemoglobin characterization; evolution; amino acid sequence; snakes; Leaf-nosed viper. |