Related Experiment Video
Updated: Jun 5, 2026
Isolation and Identification of Bacterial Strains from Skin of Terrestrial Amphibians
Published on: June 17, 2025
Isolation of a variant Porphyromonas sp. from polymicrobial infections in central bearded dragons (Pogona vitticeps)
David A Bemis1, Cheryl B Greenacre, Mary Jean Bryant
1Schubot Exotic Bird Health Center and Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, TX, USA. bemis@utk.edu
Abstract:
Isolates of gram-negative anaerobic bacteria from reptiles have only occasionally been identified to the genus and species level in the veterinary medical literature. In particular, reports identifying Porphyromonas spp. from infections in reptiles are scarce. The present report describes unique Porphyromonas isolates obtained from necrosuppurative infections in central bearded dragons (Pogona vitticeps). The isolates grew in the presence of oxygen, were strongly hemolytic, and did not produce detectable black, iron porphyrin pigment. Biochemical identification kit numeric biocodes gave high but unreliable probabilities (>99.9%) for identification as Porphyromonas gingivalis. Partial 16S ribosomal RNA gene sequences of the isolates were identical to each other and shared 91% identity with those of Porphyromonas gulae. The isolates may represent a new reptile-associated Porphyromonas species.
Insights
Unique Porphyromonas bacteria were identified in central bearded dragons with infections. These isolates, potentially a new species, challenge current reptile bacterial identification methods.
Area of Science:
- Veterinary Microbiology
- Herpetological Pathology
Background:
- Gram-negative anaerobic bacteria are infrequently identified to species level in reptiles.
- Porphyromonas species are rarely reported in reptilian infections.
Observation:
- Unique Porphyromonas isolates were recovered from central bearded dragons (Pogona vitticeps) with necrosuppurative infections.
- These isolates exhibited unusual growth in oxygen and strong hemolytic activity, lacking typical black pigment production.
- Standard biochemical identification kits yielded unreliable high probabilities for Porphyromonas gingivalis.
Findings:
- Partial 16S ribosomal RNA gene sequencing revealed isolates were identical to each other.
- The isolates shared only 91% sequence identity with Porphyromonas gulae, suggesting a novel species.
- The phenotypic characteristics (aerobic growth, hemolysis, lack of pigment) deviate from known Porphyromonas species.
Implications:
- This discovery highlights the need for advanced molecular techniques for accurate bacterial identification in reptiles.
- The findings suggest a potentially new Porphyromonas species adapted to or associated with reptiles.
- Further research is warranted to characterize this novel bacterium and its role in reptilian disease.
