Molecular Characterization and Gene Expression Profiling ... - CUSAT

Chapter 2
revealed the relation of ALF gene to other isoforms of ALF present in P.
monodon, F. indicus, F. chinensis and F. paulensis (Table 2.4 and 2.5). BLASTn
analysis of the nucleotide sequence revealed that the sequence shared 99%
similarity to the ALF isoform ALFPm3 of P. monodon for a query coverage of
98% which showed that both are the same isoforms. Great similarity was also
found to ALF isoforms of F. indicus, F. chinensis and F. paulensis also (Table
2.4). BLASTp analysis of the amino acid sequences of the ALF, also
confirmed the above results (Table 2.5).
Multiple alignments also revealed high degree of similarity among the
amino acid sequences of ALFs. Multiple alignments performed for the amino
acid sequences of ALFs that are more similar and with other known ALFs of
shrimps showed the presence of conserved sequences for these peptide
molecules. Multiple alignments confirmed the results of the BLAST analysis,
where maximum similarity was shown to ALF isoforms of P. monodon
(Fig.2.15 and 2.16).
2.3.1.2.3. Phylogenetic analysis of ALF-2
The bootstrap distance tree calculated for the resulting ALF sequences
confirmed that ALF possessed more similarity to that of other ALFs from P.
monodon than to the ALF of Fenneropenaeus and Farfantepenaeus sp. (Fig.2.17).
Phylogenetic tree drawn based on known amino acid sequences of shrimp
ALF could be divided into three groups. Group I consisted of ALFs of P.
monodon. Group II and III consisted of ALFs of Fenneropenaeus and
Farfantepenaeus sp. respectively.
Phylogenetic tree drawn based on all known ALF sequences of
decapods could be divided into five major groups Fig.2.18. Group I consisted
of shrimp ALFs, Group II and IV consisted of ALFs of lobsters, Group III
consisted of ALs of shrimsp and crabs, Group V consisted of ALFs of crabs.
Molecular Characterization and Gene Expression Profiling of Antimicrobial Peptides in Penaeid Shrimps
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