Abstract: Recombinant strains of L. johnsonii which have capacities of surviving passage through the intestine, adhering to human intestinal cells and increasing phagocytosis of macrophages and which have a sequence of gene coding which is an L. johnsonii strain sequence of gene coding for D-lactate dehydrogenase modified so that the recombinant strain produces only L(+)-lactate.

Abstract: A bacteriocin having activity against bacteria including Listeria monocytogenes is obtained by culturing cells of a strain of Micrococcus varians, particularly cells of deposited strains CNCM I-1586 and CNCM I-1587, to obtain cultured cells and a supernatant and by separating the supernatant from the cultured cells to obtain the supernatant which contains the bacteriocin which, in turn, may be isolated from the supernatant.

Abstract: A recombinant strain of L. johnsonii which has capacities of surviving passage through the intestine, adhering to human intestinal cells and increasing phagocytosis of macrophages and which has a gene sequence code for D-lactate dehydrogenase which is a modified L. johnsonii gene sequence code and which produces only L(+)-lactate.

Abstract: Micrococcus varians strains which produce a composition having bactericidal activity, including deposited strains CNCM I-1586 and CNCM I-1587 and biologically pure cultures thereof and including also strains having nucleotide sequence SEQ ID NO:2 or including nucleotides 154 to 228 of sequence SEQ ID NO:2 and which may further include amino acid sequence SEQ ID NO:1 or amino acid sequence SEQ ID NO:3.

Abstract: DNA fragment of phages which are virulent towards a Streptococcus, capable of conferring on a Streptococcus containing it resistance to at least one phage, especially a fragment homologous or hybridizing to the 3.6 kb HindIII fragment present in the plasmid CNCM I-1588 or the 6.5 kb EcoRV fragment present in the plasmid CNCM I-1589. Process for making a Streptococcus resistant to at least one phage, by cloning into a vector a DNA fragment of a phage which is virulent towards a Streptococcus, capable of conferring on a Streptococcus resistance to at least one phage and introducing the vector into a Streptococcus.

Abstract: Nucleotide fragments which encode a bacteriocin composition derived from Micrococcus varians and for preparing compositions to obtain the bacteriocin and for obtaining recombinant microorganisms. The nucleotide fragments include, in particular, nucleotides 154 to 228 and nucleotides 88 to 153 and their combination, nucleotides 88 to 228, identified in the sequence lists herein.

Abstract: An isolated peptide which in a microorganism, and particularly in Micrococcus varians, is a signal peptide which initiates expression of a bactericide composition.

Abstract: The present invention concerns a plasmid derived from Lactobacillus delbrueckii sp. comprising at least the restriction map of the FIG. 1 or portion(s) thereof; the recombinant vector comprising the said plasmid, at least one DNA sequence capable of replication into E. coli and/or Lc. lactis and at least one marker.The present invention concerns also the microorganism transformed by the said plasmid and/or by the said recombinant vector.

Abstract: Ice nucleation is promoted in an ingestible biological material by treating the material with an ice-nucleating protein carried by a yeast or lactococcal GRAS microorganism, or a fraction thereof, transformed by a plasmid vector carrying a gene coding for the ice-nucleating protein.