Plasmid-encoded functions of ropy lactic acid streptococcal strains from Scandinavian fermented milk.
Ropy Streptococcus (Lactococcus) cremoris strains isolated from a ropy Swedish sour milk ("longfil") and a ropy Finnish milk product ("Viili") were screened for their plasmid-encoded functions. Curing experiments strongly indicated that the ropy phenotype was linked to a 17-Md plasmid in the Swedish strains and to a 30 Md plasmid in the Finnish strains. Comparative restriction endonuclease analysis and DNA/DNA-hybridization studies revelated that plasmids from both strain families shared homologous DNA regions. Though be Swedish ropy strains harbored a conjugative 45-Md lactose plasmid, no cotransfer of the 17 Md plasmid occurred.
D000818:Animals; D002417:Cattle; D004269:DNA, Bacterial / Q000032:analysis; D003611:Dairy Products; D005285:Fermentation; D005516:Food Microbiology; D007785:Lactose / Q000378:metabolism*; D009693:Nucleic Acid Hybridization; D010641:Phenotype; D010957:Plasmids; D012537:Scandinavian and Nordic Countries; D013291:Streptococcus / Q000235:genetics* / Q000378:metabolism
D004269:DNA, Bacterial; D007785:Lactose