Cloning and Sequence
Analysis of cDNAs Encoding Two Acidic PLA2 from venom of Ophiophagus
hannah(King Cobra), Guangxi Species
WANG Qiu Yan
( The First Affiliated Hospital of Guangxi Medical University , Nanning 530021,
China )
SHU Yu-Yan*, ZHUANG Mao-Xing
( Guangxi Medical University, Nanning 530021, China )
LIN Zheng-Jiong
( National Laboratory of Biomacromolecules, Institute of Biophysics, the
Chinese Academy of Sciences, Beijing 100101, China )
Abstract Total RNA
was extracted from venom glands of Ophiophagus hannah, Guangxi
species. The cDNAs encoding PLA2 were amplified by RT-PCR and
cloned into the PUCm-T vector. The positive clones encoding two acidic PLA2(APLA2-1
and APLA2-2) were selected and bidirectionally sequenced. Their
complete amino acid sequences were deduced and found to be identical to the
known amino acid sequences. Their isoelectric points calculated by computer
agreed with the values determined with their protein. Homology analysis indicated
that the mature peptide of APLA2-1 had high homology with PLA2
from venoms of Ophiophagus hannah, Fujian and Taiwan species, but APLA2-2
had lower homology. The most striking difference between APLA2-2 and
other PLA2 from Ophiophagus hannah venoms is the missing of
a extra “pancreatic loop” at residues 62?6 in APLA2-2, and it may be
related to their species evolution and biological activity.
Key words Ophiophagus hannah； PLA2； gene； clone
*Corresponding author： Tel, 86-771-5350477-8549； Tel/Fax, 86-771-5353495； e-mail, [email protected]