TABLE 1.
Hybridization of full-length and central fimP (type 1) and fimA (type 2) gene probes with chromosomal DNA from Actinomyces strains of defined binding specificities
| Speciesa and strain | Originb | Degree of hybridizationc
|
Binding specificityd
|
|||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
fimP fimbrial gene
|
fimA fimbrial gene
|
|||||||||
| Full-length probe | Central probe | Full-length probe | Central probes
|
APRPs | GalNAcβ
|
Unknown structure | ||||
| 2:1 | 2:2 | 2:1 | 2:2 | |||||||
| A. naeslundii genospecies 1 | ||||||||||
| B-2-G | Buccae | 2 | 0 | 6 | 4 | 0 | − | + | − | |
| B-1-L | Buccae | 3 | 0 | 6 | 3 | 0 | − | + | − | |
| P-4-N | Plaque | 2 | 0 | 5 | 4 | 0 | − | + | − | |
| Pn-1-GA | Plaque | 2 | 0 | 6 | 4 | 0 | − | + | − | |
| Pn-22-E | Plaque | 3 | 0 | 6 | 4 | 0 | − | + | − | |
| P-5-L | Plaque | 2 | 0 | 6 | 4 | 0 | − | + | − | |
| P-10-A | Plaque | 2 | 0 | 6 | 4 | 0 | − | + | − | |
| A. naeslundii genospecies 2 | ||||||||||
| B-3-N | Buccae | 6 | 6 | 5 | 0 | 3 | + | − | + | |
| B-10-N | Buccae | 6 | 4 | 5 | 0 | 3 | + | − | + | |
| B-3-K | Buccae | 6 | 4 | 6 | 0 | 3 | + | − | + | |
| B-10-K | Buccae | 6 | 5 | 5 | 0 | 2 | + | − | + | |
| B-1-G | Buccae | 6 | 2 | 4 | 0 | 2 | + | − | + | |
| B-3-L | Buccae | 5 | 4 | 5 | 0 | 2 | + | − | + | |
| B-10-L | Buccae | 6 | 5 | 5 | 0 | 2 | + | − | + | |
| B-1-A | Buccae | 6 | 4 | 5 | 0 | 4 | + | − | + | |
| P-1-N | Plaque | 6 | 5 | 4 | 0 | 3 | + | − | + | |
| P-6-K | Plaque | 5 | 5 | 4 | 0 | 3 | + | − | + | |
| P-1-G | Plaque | 6 | 3 | 6 | 0 | 4 | + | − | + | |
| P-1-L | Plaque | 4 | 4 | 5 | 0 | 2 | + | − | + | |
| P-1-A | Plaque | 6 | 3 | 5 | 0 | 4 | + | − | + | |
| A. odontolyticus | ||||||||||
| B-4-L | Buccae | 4 | 4 | 5 | 0 | 2 | + | − | + | |
| Pn-13-N | Plaque | 3 | 0 | 3 | 0 | 0 | + | − | + | |
| T-5-G | Tongue | 3 | 0 | 2 | 0 | 0 | + | − | − | + |
| T-1-G | Tongue | 3 | 0 | 2 | 0 | 0 | − | − | − | + |
| T-21-N | Tongue | 3 | 0 | 2 | 0 | 0 | − | − | − | + |
| T-25-N | Tongue | 3 | 0 | 2 | 0 | 0 | − | − | − | + |
| T-26-N | Tongue | 3 | 0 | 2 | 0 | 0 | − | − | − | + |
| T-27-N | Tongue | 3 | 0 | 2 | 0 | 0 | − | − | − | + |
| T-1-K | Tongue | 3 | 0 | 2 | 0 | 0 | − | − | − | + |
| T-3-K | Tongue | 3 | 0 | 2 | 0 | 0 | − | − | − | + |
| T-10-K | Tongue | 2 | 0 | 1 | 0 | 0 | − | − | − | + |
| A. israelii | ||||||||||
| ATCC 10048T | 0 | 0 | 0 | 0 | 0 | |||||
| ATCC 12102T | 0 | 0 | 0 | 0 | 0 | |||||
| A. meyeri ATCC 35568T | 0 | 0 | 0 | 0 | 0 | |||||
| A. gerencseriae ATCC 23860T | 0 | 0 | 0 | 0 | 0 | |||||
| A. georgiae ATCC 49285T | 0 | 0 | 0 | 0 | 0 | |||||
| Escherichia coli | ||||||||||
| K12 | 0 | 0 | 0 | 0 | 0 | |||||
| HB101 | 0 | 0 | 0 | 0 | 0 | |||||
Strains were isolated from several individuals (last suffix in strain designations for A. naeslundii genospecies 1 and 2 and A. odontolyticus). The isolates were identified by multivariate statistical analysis of phenotypic characteristics, serological reactions, and protein banding patterns of cell extracts analyzed by SDS-PAGE (18).
Strains were isolated from the buccal mucosa (buccae), teeth (plaque), and tongue of several individuals.
The type 1 DNA probes were generated from the fimP fimbrial subunit gene of A. naeslundii T14V, and the type 2:1 and type 2:2 DNA probes were generated from the variant fimA fimbrial subunit genes of A. naeslundii ATCC 12104T (genospecies 1) and P-1-N (genospecies 2), respectively. The probes were labeled with digoxigenin and used in slot blot hybridization with chromosomal DNA from Actinomyces species under high-stringency conditions. The degree of hybridization was scored from 0 to 6 according to the following densitometric values: 0 = <0.01, 1 = 0.01 to <0.04, 2 = 0.04 to <0.10, 3 = 0.10 to <0.16, 4 = 0.16 to <0.22, 5 = 0.22 to <0.27, and 6 = ≥0.27. Essentially identical results, though analyzed for only half of the strains, were obtained under low-stringency conditions.
APRP specificity denotes binding of Actinomyces strains to APRP-1 and APRP-3 and statherin adsorbed onto hydroxyapatite beads (18, 19). Preferential binding of all strains was in the order of APRP-1 > APRP-3 > statherin. GalNAcβ specificity denotes hemagglutination and aggregation of Actinomyces strains with an established collection of streptococcal strains in a GalNAcβ1-3Galα-O-ethyl-inhibitable fashion (18, 19). The GalNAcβ specificities, types 2:1 and 2:2, denote different aggregation patterns with S. oralis Ss34 and MPB1: type 2:1 coaggregates with both strains, whereas type 2:2 coaggregates only with Ss34 (18, 19). Binding specificity to unknown structures denotes aggregation of Actinomyces with streptococci that was not inhibitable by the presence of GalNAcβ1-3Galα-O-ethyl (18, 19). +, positive result; −, negative result.