PCR/RFLP-based allelic variants of streptokinase and their plasminogen activation potencies.
PCR-restriction fragment length polymorphism (PCR/RFLP)-based analysis of β-domain variable region of streptokinase genes (sk) has previously identified 14 sk alleles (sk1-sk14) in group A (GAS), C (GCS) and G (GGS) streptococci isolates from a few geographically distinct regions. However, the relation of sk allelic variants to their plasminogen activation potencies remained as a matter of debate. Herein, employing the same PCR/RFLP assay, we analysed sk allelic variants of GAS and GCS/GGS isolates from Iranian patients. In total, 21 sk allelic variants including 14 new alleles (sk14-sk28) were identified. Results implied the horizontal gene transfer of sk fragments between GAS and GCS/GGS strains and did not prove the specificity of particular sk alleles to GCS/GGS or GAS groups. Measurement of streptokinase (SK) activity in streptococcal culture supernatants by colorimetric assay (S2251 substrate) ranged from 9 to 182 IU mL(-1). Although some strains with the highest SK activity were detected in definite variants, no significant correlation between sk alleles and plasminogen activation was detected (P value > 0.05). Analysis of DNA sequences and restriction site mapping of selective sk variants with similar SK activity pointed to the inadequacy of the currently available PCR/RFLP method for differentiation of critical/silent nucleotides to precisely categorize sk alleles for their functional properties.
Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran.
Malihe
M
Keramati
Farzin
F
Roohvand
Zahra
Z
Eslaminejad
Amir
A
Mirzaie
Vajihe Sadat
VS
Nikbin
Mohammad Mehdi
MM
Aslani
D000483:Alleles; D000704:Analysis of Variance; D001483:Base Sequence; D003124:Colorimetry; D004269:DNA, Bacterial / Q000032:analysis / Q000737:chemistry; D005798:Genes, Bacterial; D006801:Humans; D007492:Iran; D008969:Molecular Sequence Data; D010958:Plasminogen / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods*; D012150:Polymorphism, Restriction Fragment Length / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013290:Streptococcal Infections / Q000382:microbiology; D013291:Streptococcus / Q000201:enzymology / Q000235:genetics*; D013300:Streptokinase / Q000235:genetics* / Q000378:metabolism
D004269:DNA, Bacterial; D010958:Plasminogen; D013300:Streptokinase