title: Use of lytic bacteriophage for Actinomyces viscosus T14V as a probe for cell surface components mediating intergeneric coaggregation.
abstract: A lytic bacteriophage for Actinomyces viscosus T14V (the reference strain for actinomyces coaggregation group A) was isolated from raw sewage. This phage, designated BF307, also lysed the T14V-derived nonfimbriated mutant PK455-2 as well as A. viscosus MG-1 and T14AV but not the other serotype 2 or serotype 1 strains of this species that were tested or any of nine Actinomyces naeslundii isolates. Phages BF307 belonged to Bradley morphological group C and was similar in appearance to the A. viscosus MG-1 phages Av-1 and Av-3, which do not productively infect A. viscosus T14V. A. viscosus MG-1 mutants selected for resistance to phage BF307, Av-3, or CT7 (a human dental plaque isolate with the same host range as BF307) were coresistant to the other two phages but sensitive to Av-1. These results indicate that the receptors on A. viscosus MG-1 for phages BF307, Av-3, and CT7 are identical or share a common precursor and that the receptor for phage Av-1 is distinct. Comparison of the genomes of BF307, Av-3, and CT7 revealed that their DNAs were similar in size but distinguishable by restriction analysis. Two altered coaggregation phenotypes were identified among the phage BF307-resistant mutants of strains MG-1, T14V, T14AV, and PK455-2. Class I mutants had lost the ability to interact with coaggregation group 1 streptococci, and class II mutants did not coaggregate with either group 1 or group 2 streptococci. These results are consistent with the proposal that the phage BF307 receptor on these A. viscosus strains is related to one of the structures that mediates coaggregation with oral streptococci. A model to delineate the various coaggregation mediators on the surface of actinomyces coaggregation group A cells is presented, and the use of these phages to probe surface components of human oral actinomyces strains is discussed.
authors.affiliation: Department of Microbiology, School of Dentistry, University of Maryland, Baltimore 21201.
authors.forename: A L
authors.initials: AL
authors.lastname: Delisle
authors.forename: J A
authors.initials: JA
authors.lastname: Donkersloot
authors.forename: P E
authors.initials: PE
authors.lastname: Kolenbrander
authors.forename: C A
authors.initials: CA
authors.lastname: Tylenda
mesh_terms: D000190:Actinomyces / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D001426:Bacterial Proteins / Q000032:analysis / Q000494:pharmacology*; D001435:Bacteriophages / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004279:DNA, Viral / Q000032:analysis; D008242:Lysogeny; D008565:Membrane Proteins / Q000032:analysis* / Q000494:pharmacology; D011940:Receptor Aggregation; D011991:Receptors, Virus / Q000502:physiology*; D013298:Streptococcus sanguis / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D004279:DNA, Viral; D008565:Membrane Proteins; D011991:Receptors, Virus