Bacteriocin Derived from Lactobacillus Rhamnosus

Abstract

Provided is a bacteriocin that is capable of being easily mass-produced, has high antimicrobial activity even at low concentration, has a wide antimicrobial spectrum, and is less likely to produce resistant microorganisms. The bacteriocin has the amino acid sequence shown in SEQ ID NO: 1 or SEQ ID NO: 2 in SEQUENCE LISTING, or has the same amino acid sequence as shown in SEQ ID NO: 1 or SEQ ID NO: 2 in SEQUENCE LISTING except that one or several amino acids are deleted, substituted, inserted and/or added, wherein the amino acid sequence provides antimicrobial activity and the isoelectric point is not less than 12.

1 . A basic antimicrobial peptide comprising an amino acid sequence shown in SEQ ID NO: 1 or SEQ ID NO: 2, or with the same amino acid sequence as shown in SEQ ID NO: 1 or SEQ ID NO: 2 except that one or several amino acids are deleted, substituted, inserted and/or added,
 wherein the basic antimicrobial peptide is antimicrobial to cariogenic bacteria, periodontal disease bacteria and  Candida  and has an isoelectric point of not less than 12.   
     
     
         2 . (canceled) 
     
     
         3 . A composition for prophylaxis, amelioration and/or therapy of oral diseases, the composition comprising the basic antimicrobial peptide according to  claim 1 , or a pharmaceutically acceptable derivative or a pharmaceutically acceptable salt of the basic antimicrobial peptide as an effective component. 
     
     
         4 . The composition for prophylaxis, amelioration and/or therapy of oral diseases according to  claim 3 , wherein the composition for prophylaxis, amelioration and/or therapy of oral diseases is a growth inhibitor of cariogenic bacteria, periodontal disease bacteria and/or  Candida.    
     
     
         5 . A gene that encodes the basic antimicrobial peptide according to  claim 1 . 
     
     
         6 . A recombinant expression vector obtained by incorporation of the gene according to  claim 5 . 
     
     
         7 . A host cell comprising the recombinant expression vector according to  claim 6 . 
     
     
         8 . A transformant produced by transformation with the recombinant expression vector according to  claim 6 . 
     
     
         9 . The transformant according to  claim 8 , wherein the transformant is a bacterium. 
     
     
         10 . A method for producing a basic antimicrobial peptide, the method comprising:
 a culture step of culturing  Lactobacillus rhamnosus ; and   an extraction step of extracting the basic antimicrobial peptide according to  claim 1  from a bacterial cell culture obtained by the culture step.   
     
     
         11 . The method for producing a basic antimicrobial peptide according to  claim 10 , wherein the  Lactobacillus rhamnosus  is a  Lactobacillus rhamnosus  KO1 strain (Patent Microorganisms Depositary, National Institute of Technology and Evaluation (Incorporated Administrative Agency) accession No. NITE P-1065) and/or a  Lactobacillus rhamnosus  KO3 strain (Patent Microorganisms Depositary, National Institute of Technology and Evaluation (Incorporated Administrative Agency) accession No. NITE BP-771). 
     
     
         12 . The method for producing a basic antimicrobial peptide according to  claim 10 , wherein, in the culture step, killed cells of  Candida  are added. 
     
     
         13 . A  Lactobacillus rhamnosus  KO1 strain that produces the basic antimicrobial peptide according to  claim 1 . 
     
     
         14 . The method for producing a basic antimicrobial peptide according to  claim 11 , wherein, in the culture step, killed cells of  Candida  are added.