title: Macedocin, a food-grade lantibiotic produced by Streptococcus macedonicus ACA-DC 198.
abstract: Streptococcus macedonicus ACA-DC 198, a strain isolated from Greek Kasseri cheese, produces a food-grade lantibiotic named macedocin. Macedocin has a molecular mass of 2,794.76 +/- 0.42 Da, as determined by electrospray mass spectrometry. Partial N-terminal sequence analysis revealed 22 amino acid residues that correspond with the amino acid sequence of the lantibiotics SA-FF22 and SA-M49, both of which were isolated from the pathogen Streptococcus pyogenes. Macedocin inhibits a broad spectrum of lactic acid bacteria, as well as several food spoilage and pathogenic bacteria, including Clostridium tyrobutyricum. It displays a bactericidal effect towards the most sensitive indicator strain, Lactobacillus sakei subsp. sakei LMG 13558(T), while the producer strain itself displays autoinhibition when it is grown under conditions that do not favor bacteriocin production. Macedocin is active at pHs between 4.0 and 9.0, and it retains activity even after incubation for 20 min at 121 degrees C with 1 atm of overpressure. Inhibition of macedocin by proteolytic enzymes is variable.
authors.affiliation: Laboratory of Dairy Research, Department of Food Science and Technology, Agricultural University of Athens, Greece.
authors.forename: Marina D
authors.initials: MD
authors.lastname: Georgalaki
authors.forename: Erika
authors.initials: E
authors.lastname: Van Den Berghe
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Kritikos
authors.forename: Bart
authors.initials: B
authors.lastname: Devreese
authors.forename: Jozef
authors.initials: J
authors.lastname: Van Beeumen
authors.forename: George
authors.initials: G
authors.lastname: Kalantzopoulos
authors.forename: Luc
authors.initials: L
authors.lastname: De Vuyst
authors.forename: Effie
authors.initials: E
authors.lastname: Tsakalidou
mesh_terms: D000595:Amino Acid Sequence; D001419:Bacteria / Q000187:drug effects; D001430:Bacteriocins / Q000096:biosynthesis* / Q000302:isolation & purification / Q000494:pharmacology; D003470:Culture Media; D006863:Hydrogen-Ion Concentration; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D008970:Molecular Weight; D013291:Streptococcus / Q000254:growth & development / Q000378:metabolism*; D013696:Temperature
chemical_list: D001430:Bacteriocins; D003470:Culture Media; C471066:macedocin, Streptococcus macedonicus