ASCP Technologist in Microbiology (M) Practice Exam – Prep Guide & Study Questions 2026

Actinobacillus is a genus of bacteria that exhibits particular characteristics relevant to its classification and pathogenicity. The option indicating that it is an obligate intracellular pathogen is correct. This means that Actinobacillus has a growth requirement that necessitates living within the cells of a host organism to survive and replicate.

This adaptation allows Actinobacillus to evade certain host immune responses and exploit the intracellular environment for nutrients and reproduction. Obligate intracellular pathogens are often associated with specific disease processes in their hosts, which is a key point in understanding the clinical implications of infections caused by such organisms.

The other options do not accurately describe the nature of Actinobacillus. For instance, being motile and oxidase positive is not a trait associated with this genus, which typically does not exhibit significant motility and may vary in oxidase activity. Actinobacillus is also not classified as a conventional aerobic bacterium, as its metabolic pathways often differ from those of typical aerobic organisms. Lastly, while it may have parasitic tendencies as it relies on a host for growth, it does not fit the strict definition of a parasitic organism that typically lives off of host tissues in a more harmful manner.

Thus, the association of