Characterization of truncated human mannan-binding protein (MBP) expressed in Escherichia coli.
Mannan-binding protein (MBP) is a calcium-dependent mammalian serum lectin important in first-line host defense. MBP belongs to the collectin family, which is characterized by an NH2-terminal cysteine-rich domain, a collagen-like domain, a neck domain, and a carbohydrate recognition domain (CRD). We have expressed a recombinant human MBP, consisting of the short collagen region (two repeats of Gly-Xaa-Yaa amino acid sequences), the neck domain, and the CRD, in Escherichia coli. The truncated MBP was capable of forming trimers by association of the neck domain and could bind sugar with a specificity similar to that of the native form. Results of hemagglutination inhibition (HI) assay of influenza A virus showed that the truncated MBP inhibited hemagglutination less strongly, although the native MBP induced the HI phenomenon. These results suggest that an oligomeric structure is an advantage for MBP to have full biological activity against influenza A virus.
Department of Pathology, Osaka Prefectural Institute of Public Health, Japan.
S
S
Eda
Y
Y
Suzuki
T
T
Kawai
K
K
Ohtani
T
T
Kase
T
T
Sakamoto
N
N
Wakamiya
D002352:Carrier Proteins / Q000096:biosynthesis* / Q000737:chemistry; D003094:Collagen; D037222:Collectins; D004926:Escherichia coli / Q000378:metabolism*; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D009980:Influenza A virus / Q000737:chemistry; D037102:Lectins / Q000096:biosynthesis / Q000737:chemistry; D008351:Mannans / Q000096:biosynthesis / Q000737:chemistry; D011994:Recombinant Proteins / Q000096:biosynthesis; D012091:Repetitive Sequences, Nucleic Acid; D014764:Viral Proteins / Q000378:metabolism
D002352:Carrier Proteins; D037222:Collectins; D037102:Lectins; D008351:Mannans; C057959:NA glycoprotein, Influenza B virus; D011994:Recombinant Proteins; D014764:Viral Proteins; D003094:Collagen