title: Milk protein fragments induce the biosynthesis of macedocin, the lantibiotic produced by Streptococcus macedonicus ACA-DC 198.
abstract: The aim of the present work was to study the mode of the induction of the biosynthesis of macedocin, the lantibiotic produced by Streptococcus macedonicus ACA-DC 198. Macedocin was produced when the strain was grown in milk but not in MRS or M17 broth. No autoinduction mechanism was observed. Production did not depend on the presence of lactose or galactose in the culture medium or on a coculture of the producer strain with macedocin-sensitive or macedocin-resistant strains. Induction seemed to depend on the presence of one or more heat-stable protein components produced when S. macedonicus ACA-DC 198 was grown in milk. The partial purification of the induction factor was performed by a combination of chromatography methods, and its activity was confirmed by a reverse transcription-PCR approach (RT-PCR). Mass spectrometric (MS) and tandem mass spectrometric (MS/MS) analyses of an induction-active fraction showed the presence of several peptides of low molecular mass corresponding to fragments of alpha(S1)- and beta-casein as well as beta-lactoglobulin. The chemically synthesized alpha(S1)-casein fragment 37-55 (2,253.65 Da) was proven to be able to induce macedocin biosynthesis. This is the first time that milk protein degradation fragments are reported to exhibit a bacteriocin induction activity.
authors.affiliation: Department of Food Science and Technology, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece.
authors.forename: Marina
authors.initials: M
authors.lastname: Georgalaki
authors.forename: Marina
authors.initials: M
authors.lastname: Papadelli
authors.forename: Elina
authors.initials: E
authors.lastname: Chassioti
authors.forename: Rania
authors.initials: R
authors.lastname: Anastasiou
authors.forename: Anastassios
authors.initials: A
authors.lastname: Aktypis
authors.forename: Luc
authors.initials: L
authors.lastname: De Vuyst
authors.forename: Gonzalez
authors.initials: G
authors.lastname: Van Driessche
authors.forename: Bart
authors.initials: B
authors.lastname: Devreese
authors.forename: Effie
authors.initials: E
authors.lastname: Tsakalidou
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001430:Bacteriocins / Q000096:biosynthesis* / Q000235:genetics; D001483:Base Sequence; D014408:Biomarkers, Tumor; D002364:Caseins / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology; D003470:Culture Media; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D005516:Food Microbiology; D005798:Genes, Bacterial; D066298:In Vitro Techniques; D007782:Lactoglobulins / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology; D008894:Milk Proteins / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology; D010447:Peptide Hydrolases; D013291:Streptococcus / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D053719:Tandem Mass Spectrometry; D000951:Antigens, Neoplasm
chemical_list: D001430:Bacteriocins; D014408:Biomarkers, Tumor; D002364:Caseins; D003470:Culture Media; D017931:DNA Primers; D004269:DNA, Bacterial; D007782:Lactoglobulins; D008894:Milk Proteins; D010446:Peptide Fragments; D010447:Peptide Hydrolases; C115012:human epithelial antigen-125; D000951:Antigens, Neoplasm; C471066:macedocin, Streptococcus macedonicus