Delta, Epsilon, - Non-Proteobacteria

Gram Negative Bacteria

Delta Proteobacteria

  • Bdellovibrio sp.

    • Consumes other gram-negative bacteria

  • Myxococcus

    • Exhibits a complex life cycle

    • Neither are pathogenic

Epsilon Proteobacteria

  • Campylobacter sp.

    • Characterized by curved, bipolar, or unipolar flagella

    • Infects the jejunal ileum border of the intestine, allowing growth and reproduction

Helicobacter sp.

  • Infects the stomach lining

  • Helicobacter sp.

    • Capable of drilling into the mucosal layer, which protects it from stomach acid

    • Reproduction can cause inflammation, leading to severe damage

      • Damaged cells may leak blood, resulting in bleeding ulcers

Non-Proteobacteria

  • Bacteroides sp.

  • Chlamydia sp.

  • Treponema sp.

  • Borrelia sp.

Chlamydia sp.

  • 2nd most common STI

  • Obligate parasite with a binding affinity to cause disease

  • Causes Pelvic Inflammatory Disease

  • Can lead to Ophthalmic Neonatorum (eye infection in newborns)

  • Exhibits an elementary intracellular body shape

  • Reproduces within host cells

Treponema sp.

General Information

  • Type: Non-Proteobacteria

  • Treponema pallidum

    • Spirochete responsible for syphilis

    • 3rd most common STI

Phases of Syphilis

  1. Primary Syphilis

    • Occurs as early as 9 days up to 3 months

    • Characterized by the appearance of a hard chancre on the genitalia

  2. Secondary Syphilis

    • Occurs between 3 weeks to 6 months (average is 6 weeks)

    • S&S (signs & symptoms) are more profuse and intense

    • Includes fever, headache, sore throat, and red/brown skin rash

  3. Latency and Tertiary Syphilis

    • Can last for more than 20 years!

    • Manifested by ulcerating syphilis tumors (gummas)

    • Can spread to many organs

Borrelia sp.

General Information

  • Type: Non-Proteobacteria

  • Borrelia burgdorferi

    • Causative agent of Lyme Disease, named after a small town in Connecticut

Lifecycle of Borrelia burgdorferi

  1. Larval Stage

    • Newly hatched larvae become infected when they feed on small animals (e.g., mice) that harbor the spirochete

  2. Nymph Stage

    • Infected larvae molt into aggressive feeding nymphs in the second year

    • Commonly transmitted by ticks to humans (accidental host)

    • Early S&S includes rash and lesions at the bite site, known as erythema migrans, exhibiting a bull's-eye pattern

  3. Adult Ticks

    • Nymphs mature into adult male and female ticks, which mate

    • Females lay eggs in plant litter, completing the lifecycle