Cloning and sequencing of the gene for alpha antigen from Mycobacterium avium and mapping of B-cell epitopes.
The complete nucleotide sequence of alpha antigen secreted from Mycobacterium avium (A-alpha) was determined. The gene encodes 330 amino acids, including 40 amino acids for the signal peptide, followed by 290 amino acids for the mature protein with a molecular mass of 30,811 Da. This is the first sequence of A-alpha. Comparisons between A-alpha and alpha antigens of Mycobacterium leprae, Mycobacterium bovis BCG, and Mycobacterium kansasii showed highly homologous regions which suggested a conserved functional domain and two less-homologous regions. Serological analysis of recombinant A-alpha, expressed by a series of deletion constructs, indicated the possibility that A-alpha carries at least six B-cell epitopes. The three antigenic determinants were common to Mycobacterium tuberculosis, M. kansasii, and M. avium. The results also suggested the possibility that there are three species-specific epitopes.
Ohara
N
N
School of Dentistry, Nagasaki University, Japan.
Matsuo
K
K
Yamaguchi
R
R
Yamazaki
A
A
Tasaka
H
H
Yamada
T
T
D000595:Amino Acid Sequence; D000907:Antibodies, Bacterial / Q000276:immunology*; D000942:Antigens, Bacterial / Q000235:genetics*; D001402:B-Lymphocytes / Q000276:immunology*; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D000939:Epitopes; D005798:Genes, Bacterial; D006801:Humans; D008969:Molecular Sequence Data; D009162:Mycobacterium avium / Q000235:genetics / Q000276:immunology*; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D011993:Recombinant Fusion Proteins / Q000276:immunology; D015183:Restriction Mapping; D016415:Sequence Alignment
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D004269:DNA, Bacterial; D000939:Epitopes; D009838:Oligodeoxyribonucleotides; D011993:Recombinant Fusion Proteins; C052242:alpha antigens, Mycobacterium