Gram-Negative Bacteria (Aerobic, Motile, Helical/Vibrioid Gram-Negative Bacteria)

Aerobic, Motile, Helical/Vibrioid Gram-Negative Bacteria

Rigid, helical shape or curved rods.

Lack axial filaments (endoflagella); possess polar flagella instead.

Aerobic, Motile, Helical/Vibrioid Gram-Negative Bacteria

Most are harmless aquatic organisms.

Azospirillum & Bdellovibrio

Notable Genera of Aerobic, Motile, Helical/Vibrioid Gram-Negative Bacteria:

Azospirillum

Function: Nitrogen-fixing bacteria in soil

Azospirillum

Ecological Role: Forms symbiotic relationships with plants, converting atmospheric nitrogen into a usable form for plant growth

Bdellovibrio

Function: Predatory bacterium

Bdellovibrio

Mechanism: Invades other Gram-negative bacteria, replicates inside them, and causes lysis of the host cell

Bdellovibrio

Significance: Potential biocontrol agent against harmful bacterial populations in agriculture and clinical settings

Adhesins, Cytotoxins, Endotoxin (Lipid A)

Virulence Factors of Campylobacter jejuni:

Intracellular Survival of Campylobacter jejuni

Can enter and persist inside host cells after endocytosis, helping it evade immune responses and sustain infection.

Motility and Pathogenicity of Campylobacter jejuni

Uses polar flagella for motility. Nonmotile mutants are avirulent, emphasizing the importance of motility in disease causation.

Campylobacteriosis

Disease of Campylobacter jejuni

Watery or bloody diarrhea, abdominal cramps, fever, and sometimes vomiting.

symptoms of Campylobacter jejuni

Ingestion of contaminated food (especially undercooked poultry), water, or unpasteurized milk.

Transmission of Campylobacter jejuni (Campylobacteriosis)

Stool culture under microaerophilic conditions; PCR for confirmation.

Diagnosis of Campylobacter jejuni (Campylobacteriosis)

Mild cases are self-limiting & Severe or prolonged cases may require Azithromycin.

Treatment of Campylobacter jejuni (Campylobacteriosis)

Azithromycin

drug for severe or prolonged cases of campylobacter jejuni (Campylobacteriosis)

Ensure proper food handling, avoid undercooked poultry, and practice good kitchen hygiene.

Prevention of Campylobacter jejuni (Campylobacteriosis)

Adhesins

attach/ unable GIT

cytotoxins

toxic to the cells

endotoxon (Lipid A)

trigger antiinflamatory response

Peptic Ulcer Disease (PUD)

accumulation of acid

Responsible for most gastric and duodenal ulcers in humans.

Cause of Helicobacter Pilori (Peptic ulcer Disease (PUD))

Abdominal pain (especially after meals or when stomach is empty); Heartburn, indigestion, nausea; Vomiting , weight loss, fatigue; Dark or bloody stools (indicative of GI bleeding)

Symptoms of Helicobacter Pilori (Peptic Ulcer Disease (PUD))

Family history of ulcers, tobacco use, chronic NSAID or aspirin use, excessive alcohol intake

Risk Factors of Helicobacter Pilori (Peptic Ulcer Disease (PUD))

Urea breath test (non-invasive), Stool antigen test, Endoscopic biopsy with urease test

Diagnosis of Helicobacter Pilori (Peptic ulcer disease (PUD))

Omeprazole, Pantoprazole, Esomeprazole

PPI + bismuth + metronidazole +tetracycline

PP1 + bismuth + metronidazole + tetracycline

Quadruple therapy

zole

antifungal

bismuth + metronidazole + tetracycline

triple therapy

Triple therapy with clarithromycin-based regimen (if no resistance)

alternative treatment for Helicobacter Pilori (Peptic ulcer disease (PUD))

 ood hygiene practices, Sanitation and proper food handling, Limiting NSAID use and lifestyle modification

Prevention of Helicobacter Pilori (Peptic Ulcer Disease (PUD))

Spontaneous abortion and infertility in animals

Primary disease of Campylobacter fetus

Primarily affects cattle and sheep

hosts of Campylobacter fetus

Venereal transmission or via contaminated instruments and environment

Transmission of Campylobacter fetus

Rare but may cause bacteremia, especially in immunocompromised patients

human impact of Campylobacter fetus

Good herd management, Artificial insemination using screened semen, Vaccination in livestock

Prevention in Animals of Campylobacter fetus

Low, but proper handling of infected animals and use of protective equipment is advised

Zoonotic Potential of Campylobacter fetus

Campylobacter jejuni, Helicobacter pilori, Campylobacter fetus

Aerobic, Motile, Helical/Vibrioid Gram-Negative Bacteria: