DNA analysis of the genes encoding acidocin LF221 A and acidocin LF221 B, two bacteriocins produced by Lactobacillus gasseri LF221

Autor: Majhenič, A.Č., Venema, K., Allison, G.E., Matijašić, B.B., Rogelj, I., Klaenhammer, T.R.
Přispěvatelé: TNO Voeding
Jazyk: angličtina
Rok vydání: 2004
Předmět:
molecular cloning
sequence analysis
polymerase chain reaction
Codon
Initiator

Sequence Homology
thermophilin b
Negibacteria
lactacin f
open reading frame
acidocin lf221 a
Lactobacillus gasseri
Bacteriocins
gassericin x
Cloning
Molecular

Bacteria (microorganisms)
probiotic agent
acidocin lf221 b
Southern blotting
article
bacterium
unclassified drug
genetic code
Health
Codon
Terminator

Promoter Regions (Genetics)
bacterial gene
amino acid
Plasmids
DNA
Bacterial

structural gene
Molecular Sequence Data
DNA sequence
DNA determination
Physiological Sciences
Protein Sorting Signals
Open Reading Frames
bacteriocin
food preservative
brochocin b
Animalia
controlled study
Amino Acid Sequence
nonhuman
Base Sequence
Probiotics
nucleotide sequence
lactococcin n
Sequence Analysis
DNA

bacterial strain
Lactobacillus
Genes
Bacterial

amino terminal sequence
Zdroj: Applied Microbiology and Biotechnology, 6, 63, 705-714
Popis: Lactobacillus gasseri LF221, an isolate from the feces of a child, produces two bacteriocins. Standard procedures for molecular techniques were used to locate, clone and sequence the fragments of LF221 chromosomal DNA carrying the acidocin LF221 A and B structural genes, respectively. Sequencing analysis revealed the gene of acidocin LF221 A to be an open reading frame encoding a protein composed of 69 amino acids, including a 16-amino-acid N-terminal extension. The acidocin LF221 B gene was found to encode a 65-amino-acid bacteriocin precursor with a 17-amino-acid N-terminal leader peptide. DNA homology searches showed similarities of acidocin LF221 A to brochocin B, lactococcin N and thermophilin B, whereas acidocin LF221 B exhibited some homology to lactacin F and was virtually identical to gassericin X. The peptides encoded by orfA1 and orfB3 showed characteristics of class II bacteriocins and are suspected to be the complementary peptides of acidocin A and B, respectively. orfA3 and orfB5 are proposed to encode putative immunity proteins for the acidocins. Acidocin LF221 A and acidocin LF221 B are predicted to be members of the two-component class II bacteriocins, where acidocin LF221 A appears to be a novel bacteriocin. L. gasseri LF221 is being developed as a potential probiotic strain and a food/feed preservative. Detailed characterization of its acidocins is an important piece of background information useful in applying the strain into human or animal consumption. The genetic information on both acidocins also enables tracking of the LF221 strain in mixed populations and complex environments.
Databáze: OpenAIRE