9+ Lactose Fermenting Bacteria Examples: Detailed Explanations And Images

In this article, we will be discussing lactose fermenting bacteria examples

The bacteria that ferment lactose and produce hydrogen sulfide are called lactose fermenting bacteria.

Escherichia coli

Escherichia coli are a rod-shaped gram-negative bacterium that is usually found in the lower intestine of human beings and the gut of certain animals like deer, pig, dog, cattle, sheep, and poultry. Most the E.coli are harmless and help in keeping the digestive tract healthy but some strains cause food poisoning, urinary tract infections, and diarrhea. Certain strains of E.coli produce a toxin called Shiga which damages the wall of the intestine and causes vomiting, abdominal cramps, and kidney failure. The bacteria can be transmitted through contaminated water, uncooked meat, untreated milk, and vegetables. The bacteria is anaerobic, it ferments lactose and produces hydrogen sulfide.

lactose fermenting bacteria examples
Escherichia coli Bacteria from Shutterstock

Escherichia adecarboxylata

Escherichia adecarboxylata also called Leclercia adecarboxylata is a disease-causing bacteria that resembles E.coli. It is a motile gram-negative bacterium found in the gut of animals. They usually cause diseases like Pneumonia, cellulitis, Pharyngeal abscess, and cholecystitis in immunocompromised patients.

Citrobacter koseri

Citrobacter koseri is an anaerobic, motile, gram-negative, rod-shaped non-spore-forming bacteria normally found in the gut of animals and humans. The bacteria can cause urinary tract infections in adults and meningitis in infants. Citrobacter koseri is transmitted from mother to child during birth through vaginal infections.

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Citrobacter koseri from Shutterstock

Citrobacter freundii

Citrobacter freundii is a gram-negative rod-shaped coliform bacterium that is transmitted through contaminated food. It usually causes diarrhea, urinary tract infection, pneumonia, and at times intracranial abscesses and meningitis.

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Citrobacter freundii from Shutterstock

Citrobacter farmeri

Citrobacter farmer is a gram-negative bacterium that is transmitted from infected mother to child during birth and through contaminated food and water. The bacteria usually cause sepsis, pulmonary infections, and meningitis in neonates and young children and urinary tract infections in adults.

Klebsiella pneumoniae

Klebsiella pneumoniae is a non-motile, encapsulated, gram-negative bacterium that usually resides in the gut but causes infection once it moves outside the gut region. They are transmitted through direct contact with an infected person and through contaminated medical equipment like catheters and ventilators. If the bacteria enter the respiratory tract it causes pneumonia and also causes other infections like meningitis and cellulitis.

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Klebsiella pneumoniae from Shutterstock

Klebsiella oxytoca

Klebsiella oxytoca is gram-negative rod-shaped that naturally occurs in the nose, mouth, and intestinal tract. If they are present inside the gut they are considered healthy bacteria but once it comes out it causes serious infections. The bacterium causes soft tissue infection, pneumonia, urinary tract infection, and septicemia that leads to septic shock.

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Klebsiella oxytoca from Shutterstock

Klebsiella granulomatis

Klebsiella granulomatis is a rod-shaped, aerobic, gram-negative bacterium that causes a sexually transmitted disease called Granuloma inguinale. It causes chronic inflammation in the genital areas, initially, it develops as a painless lump and later it breaks down to form a sore.

stock photo bacteria klebsiella granulomatis the causative agent of sexually transmitted disease granuloma 1202581522
Klebsiella granulomatis from Shutterstock

Klebsiella variicola

Klebsiella variicola is a non-motile rod-shaped gram-negative bacterium that forms circular, convex, and mucoid colonies. They cause urinary tract infections and respiratory tract infections. These are closely related to Klebsiella pneumonia and are usually found in plants.

Klebsiella ozaenae

Klebsiella ozaenae is a rod-shaped gram-negative bacterium that causes a chronic disease called Ozena that destroys the mucosa of the nasal cavity. The other infections caused by the bacteria are pneumonia, otitis media, rhinitis, and urinary tract infection. The bacteria spread through person-person contact. This mostly affects immunocompromised patients in the nasopharynx region.

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Klebsiella ozaenae from Shutterstock

Serratia plymuthica

Serratia plymuthica is an anaerobic, gram-negative rod-shaped bacterium that is usually found in the roots of coconut and fig trees. They are usually transmitted through contaminated respiratory equipment and catheters. The infection caused by the bacteria is chronic osteomyelitis and sepsis.

Serratia liquefaciens

Serratia liquefaciens is a motile straight rod-shaped gram-negative bacterium that is usually found in soil, water, plants, and the gut of insects, fish, rodents, and human beings. The bacteria cause urinary tract infection, meningoencephalitis, pneumonia, bloodstream infections, and sepsis. The bacteria are transmitted through contaminated water, uncooked meat, and untreated milk.

3 sem of serratia liquefaciens scimat
Serratia liquefaciens from Pixels

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