Amino acid determinants conferring stable sialidase activity at low pH for H5N1 influenza A virus neuraminidase.
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ABSTRACT:
SUBMITTER: Takahashi T
PROVIDER: S-EPMC3642167 | biostudies-literature | 2012
REPOSITORIES: biostudies-literature
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Amino acid determinants conferring stable sialidase activity at low pH for H5N1 influenza A virus neuraminidase.
Takahashi Tadanobu T Nidom Chairul A CA Quynh Le Mai Thi MT Suzuki Takashi T Kawaoka Yoshihiro Y
FEBS open bio 20120905
Avian influenza A viruses (IAVs) and human 1918, 1957, and 1968 pandemic IAVs all have neuraminidases (NAs) that are stable at low pH sialidase activity, yet most human epidemic IAVs do not. We examined the pH stability of H5N1 highly pathogenic avian IAV (HPAI) NAs and identified amino acids responsible for conferring stability at low pH. We found that, unlike other avian viruses, most H5N1 IAVs isolated since 2003 had NAs that were unstable at low pH, similar to human epidemic IAVs. These H5N1 ...[more]
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