Final answer:
To detect species that produce streptolysin O, running hemolysis tests is the most appropriate method. These tests clearly identify a bacterium's hemolytic activity, which is a characteristic of β-hemolytic streptococci like Streptococcus pyogenes that produce streptolysin O.
Step-by-step explanation:
To detect species that produce streptolysin O only, the most appropriate method is to run hemolysis tests. These tests, particularly on Blood Agar Plates, will identify whether a bacterium is β-hemolytic, which is indicative of Streptococcus pyogenes, a bacterium known to produce streptolysin O. Group A streptococci exhibit this β-hemolysis pattern and can be classified using the Lancefield grouping based on serological tests. However, for the specific detection of streptolysin O production, hemolysis tests offer a direct observation of the lysing effect on red blood cells.
Serological tests and biochemical assays are indeed important in bacterial identification, providing insights into the bacteria's physiological properties, but for streptolysin O, the hemolytic activity is the defining characteristic. Bergey's Manual of systematic bacteriology lists criteria for bacterial identification, starting with Gram stain reaction and followed by various metabolic activities that can be detected through biochemical assays. While those methods contribute to a broader understanding of bacterial identity, hemolysis remains the most direct method to confirm streptolysin O production.