Complete amino acid sequence of globin chains and biological activity of fragmented crocodile hemoglobin (Crocodylus siamensis).
Hemoglobin, α-chain, β-chain and fragmented hemoglobin of Crocodylus siamensis demonstrated both antibacterial and antioxidant activities. Antibacterial and antioxidant properties of the hemoglobin did not depend on the heme structure but could result from the compositions of amino acid residues and structures present in their primary structure. Furthermore, thirteen purified active peptides were obtained by RP-HPLC analyses, corresponding to fragments in the α-globin chain and the β-globin chain which are mostly located at the N-terminal and C-terminal parts. These active peptides operate on the bacterial cell membrane. The globin chains of Crocodylus siamensis showed similar amino acids to the sequences of Crocodylus niloticus. The novel amino acid substitutions of α-chain and β-chain are not associated with the heme binding site or the bicarbonate ion binding site, but could be important through their interactions with membranes of bacteria.
Protein and Proteomics Research Group, Department of Biochemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand.
Saowaluck
S
Srihongthong
Anawat
A
Pakdeesuwan
Sakda
S
Daduang
Tomohiro
T
Araki
Apisak
A
Dhiravisit
Sompong
S
Thammasirirak
D000489:Alligators and Crocodiles; D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D002176:Candida albicans / Q000187:drug effects; D017124:Conserved Sequence; D052978:Disk Diffusion Antimicrobial Tests; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000648:ultrastructure; D006454:Hemoglobins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D010802:Phylogeny; D021122:Protein Subunits / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D059748:Proteolysis; D030162:Reptilian Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D020539:Sequence Analysis, Protein
D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D000975:Antioxidants; D006454:Hemoglobins; D010446:Peptide Fragments; D021122:Protein Subunits; D030162:Reptilian Proteins