Thermo Scientific™ Biochemical Identification System (O.B.I.S.) Campy, 60 Tests

The Thermo Scientific™ Oxoid™ Biochemical Identification System (O.B.I.S.) Campy provides a rapid and reliable method to differentiate Campylobacter, Helicobacter, and Arcobacter species from other Gram-negative organisms. This colorimetric biochemical test is based on the detection of L-alanyl aminopeptidase (L-ALA) activity, combined with a Gram-lysis test to confirm Gram status.

The system is designed for use in clinical, food safety, veterinary, and public health microbiology laboratories, where rapid confirmation of Campylobacteraceae is essential. Results are delivered in as little as 6 minutes, streamlining diagnostic workflows and supporting accurate clinical decision-making.

Key Features & Benefits

• Rapid Differentiation: Confirms Campylobacter, Helicobacter, and Arcobacter within 6 minutes.
• Biochemical Basis: Detects absence of L-ALA enzyme activity characteristic of Campylobacteraceae.
• Dual Function Test: Includes Gram-lysis reagent to quickly determine Gram status.
• Simple Protocol: Easy-to-interpret colorimetric endpoint (purple = L-ALA positive; no color = presumptive Campylobacteraceae).
• Improved Safety & Efficiency: Closed reagent system minimizes contamination risk and reduces handling errors.
• Quality Controlled: Each kit includes recommended QC organisms and procedures for test validity.

Applications

• Clinical Diagnostics: Rapid identification of Campylobacter jejuni, C. coli, Helicobacter spp., and Arcobacter spp. from clinical isolates.
• Food Safety Testing: Confirmation of Campylobacter from poultry and food samples in routine food microbiology labs.
• Veterinary Microbiology: Screening animal specimens for Campylobacteraceae.
• Public Health Surveillance: Monitoring outbreaks of enteric pathogens in epidemiological investigations.

Test Principles

1. Gram-Lysis Test (Gram Status Confirmation)

• Uses 0.5 M NaOH (or KOH) to detect DNA stringing.
• Positive (Gram-negative): Viscous mixture and DNA string present.
• Negative (Gram-positive): No string formation, suspension remains clear.

2. L-ALA Test (Biochemical Differentiation)

• After Gram-negative confirmation, the colony is applied to the test card.
• Addition of buffer and developer produces a purple color within 20 seconds if L-ALA enzyme is present.
• Result Interpretation:
  • Positive (purple): Organism is not Campylobacter, Helicobacter, or Arcobacter.
  • Negative (no color): Presumptive Campylobacteraceae.

Quality Control Recommendations

• Gram-Lysis Positive Control: Campylobacter jejuni ATCC™ 33291™
• Gram-Lysis Negative Control: Bacillus cereus ATCC™ 11778™
• L-ALA Positive Control: Pseudomonas aeruginosa ATCC™ 27853™
• L-ALA Negative Control: Campylobacter jejuni ATCC™ 33291™

Technical Specifications

References

1. Hoosain, N. & Lastovica, A. J. (2005). Evaluation of the Oxoid Biochemical Identification System (O.B.I.S.) for differentiation of Campylobacter and Arcobacter from other Gram-negative organisms. 13th International Workshop on Campylobacter, Helicobacter and Related Organisms. Griffith University, Australia.
2. Carlone, G. M., Valadez, M. J., & Pickett, M. J. (1982). Methods for distinguishing Gram-positive from Gram-negative bacteria. J. Clin. Microbiol., 16(6), 1157–1159.

The Thermo Scientific™ O.B.I.S. Campy system offers a fast, simple, and reliable colorimetric test for distinguishing Campylobacter, Helicobacter, and Arcobacter from other Gram-negative bacteria. By combining biochemical L-ALA detection with a rapid Gram-lysis test, it reduces turnaround time from hours to minutes, supporting accurate diagnostics, food safety monitoring, and outbreak investigation workflows.