TY - JOUR
T1 - Isolation and characterization of the lantibiotic salivaricin A and its structural gene salA from Streptococcus salivarius 20P3
AU - Ross, K. F.
AU - Ronson, C. W.
AU - Tagg, J. R.
PY - 1993
Y1 - 1993
N2 - A bacteriocin-like inhibitory substance, salivaricin A, was purified from cultures of Streptococcus salivarius 20P3 and was shown by ion spray mass spectrometry to have a molecular mass of 2,315 ± 1.1 Da. Amino acid composition analysis demonstrated the presence of lanthionine, indicating that salivaricin A may be a member of the lantibiotic class of antibiotic substances. The sequence of eight amino acids at the N terminus of the molecule was determined by Edman degradation, and mixed oligonucleotide probes based on part of this sequence (GSGWIA) were used to detect the salivaricin A structural gene. A 6.2-kb EcoRI fragment of chromosomal DNA from strain 20P3 that hybridized with the probes was cloned, and the hybridizing region was further localized to a 379-bp DraI-AluI fragment. Analysis of the nucleotide sequence of this fragment indicated that salivaricin A is synthesized as a 51-amino-acid prepeptide that is posttranslationally modified and cleaved to give a biologically active 22- residue peptide containing one lanthionine and two β-methyllanthionine residues. The secondary structure of presalivaricin A was predicted to be similar to that of type A lantibiotics, with a hydrophilic α-helical leader sequence and a propeptide region with potential for β-turn formation and a lack of α-helicity. The sequence around the cleavage site of presalivaricin A differed from that of other type A lantibiotics but was similar to that of several bacteriocin-like inhibitory substances produced by lactic acid bacteria.
AB - A bacteriocin-like inhibitory substance, salivaricin A, was purified from cultures of Streptococcus salivarius 20P3 and was shown by ion spray mass spectrometry to have a molecular mass of 2,315 ± 1.1 Da. Amino acid composition analysis demonstrated the presence of lanthionine, indicating that salivaricin A may be a member of the lantibiotic class of antibiotic substances. The sequence of eight amino acids at the N terminus of the molecule was determined by Edman degradation, and mixed oligonucleotide probes based on part of this sequence (GSGWIA) were used to detect the salivaricin A structural gene. A 6.2-kb EcoRI fragment of chromosomal DNA from strain 20P3 that hybridized with the probes was cloned, and the hybridizing region was further localized to a 379-bp DraI-AluI fragment. Analysis of the nucleotide sequence of this fragment indicated that salivaricin A is synthesized as a 51-amino-acid prepeptide that is posttranslationally modified and cleaved to give a biologically active 22- residue peptide containing one lanthionine and two β-methyllanthionine residues. The secondary structure of presalivaricin A was predicted to be similar to that of type A lantibiotics, with a hydrophilic α-helical leader sequence and a propeptide region with potential for β-turn formation and a lack of α-helicity. The sequence around the cleavage site of presalivaricin A differed from that of other type A lantibiotics but was similar to that of several bacteriocin-like inhibitory substances produced by lactic acid bacteria.
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U2 - 10.1128/aem.59.7.2014-2021.1993
DO - 10.1128/aem.59.7.2014-2021.1993
M3 - Article
C2 - 8357242
AN - SCOPUS:0027279657
SN - 0099-2240
VL - 59
SP - 2014
EP - 2021
JO - Applied and environmental microbiology
JF - Applied and environmental microbiology
IS - 7
ER -