PetriKey

Bacterium

Chlamydia trachomatis

Obligate intracellular bacterium

kluh-MID-ee-uh truh-KOH-muh-tis

bacteriaintracellularelementary-bodyreticulate-bodysti

High-yield clue

Obligate intracellular + elementary body/reticulate body vocabulary.

Overview

An obligate intracellular bacterium used to teach elementary/reticulate body vocabulary and NAAT testing terminology.

Classification

  • Obligate intracellular bacterium
  • Atypical cell-wall concept

Lab & identification clues

  • NAAT vocabulary
  • Intracellular inclusion concept
  • Gram stain is not the main study anchor

Associations

  • STI screening vocabulary
  • Trachoma vocabulary
  • Neonatal conjunctivitis vocabulary

Commonly confused with

  • Neisseria gonorrhoeae
  • Mycoplasma pneumoniae

Your notes

Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.

OpenStax: Microbiology 2e organism classification foundationssourceNCBI Bookshelf: Medical Microbiology organism chapterssourceCDC: CDC disease and public-health topic pagessource