Bacteriology 9&10: Lacto, Bacilli, Coryne, Propio, Clostri, Tanne, Proph, Prevo

Question 1

Lactobacillus
-gram +/-
-shape
-w or w/o O2
-what do they produce

Answer 1

-gram (+)
-rod shaped
-facultative anaerobes
-lactic acid production

Question 2

Lactobacillus possible benefits and pathogenic sequelas

Answer 2

**possible benefits induced by lactobacillus in humans against virulence factors of pathogenic species **
-oral cavity
-skin
-GI tract
-Urogenital tract
-systemic infections

opportunistic pathogen
-lactobacillus bacteremia, liver and dental abscesses, endocarditis, prosthetic knee infections

Question 3

Which bacteria displays antibiotic, anti cancer and immunosuppressant properties?

Answer 3

Lactobacillus

They provide possible benefits against virulence factors of pathogens, but they are also opportunistic pathogens

Question 4

Acquisition of Lactobacillus

Answer 4

Vaginal delivery during birth

Question 5

Bacillus anthracis
-Gram +/-
-shape + capsule type + distinct feature
-w or w/o O2

Answer 5

Gram (+)
Rod
Facultative anaerobic (can survive) / obligate aerobe (thrives)

ENDOSPORE!!!! Spore- forming bacteria which are highly resistant to environmental conditions such as heat, radiation, and chemicals. These spores can persist in soil for years and are a key factor in its ability to spread

POLYPEPTIDE CAPSULE = anthracis produces a capsule composed of poly-D-glutamic acid, which helps it evade the host’s immune system.

Question 6

Bacillus anthracis pathogenesis

Answer 6

Unique capsule = polypeptide capsule = Antiphagocytic

Exotoxins = edema toxin and lethal toxin

Cutaneous anthrax vs. pulmonary anthrax (woolsorters disease)

ENDOSPORE!!!! Spore- forming bacteria which are highly resistant to environmental conditions such as heat, radiation, and chemicals. These spores can persist in soil for years and are a key factor in its ability to spread

POLYPEPTIDE CAPSULE = anthracis produces a capsule composed of poly-D-glutamic acid, which helps it evade the host’s immune system.

Question 7

Cutaneous anthrax

Answer 7

Bacillus anthracis is the bacteria
-95% of human anthrax = The most common form

occurring when spores enter a cut or abrasion. It typically presents as a painless ulcer with a characteristic black center (eschar). Without treatment, it can progress to severe systemic illness = septicemia

Question 8

Pulmonary anthrax (woolsorter’s disease)

Answer 8

Bacillus anthracis

The most dangerous form, occurring from inhaling spores.
rapidly progresses to severe respiratory distress, shock, and often death if not treated promptly. (Lymphadenitis and mediastinitis)

ENDOSPORE!!!! Spore- forming bacteria which are highly resistant to environmental conditions such as heat, radiation, and chemicals. These spores can persist in soil for years and are a key factor in its ability to spread

POLYPEPTIDE CAPSULE = anthracis produces a capsule composed of poly-D-glutamic acid, which helps it evade the host’s immune system.

Question 9

Medication for cutaneous anthrax and pulmonary anthrax

Answer 9

cutaneous anthrax
-Ciprofloxacin = Fluroquinolones = DNA gyrase inhibitor

pulmonary anthrax
Multi-drug therapy
-Ciprofloxacin + Clindamycin (50S) + Rifampin (RNA poly)
-Ciprofloxacin + Clindamycin + Vancomycin ( PG’s synthesis)

Question 10

Corynebacterium Diphtheriae
-gram +/-
-shape
-w/ or w/o O2
-distinct feature

Answer 10

-gram (+)
-rod “Chinese letter appearance”
-facultative anaerobic
-The pathogenicity of C. diphtheriae is largely due to the diphtheria toxin it produces. This toxin is a potent exotoxin!!!!!

Diphtheria = acute respiratory or cutaneous disease

Question 11

Describe the primary localized manifestations of diphtheria caused by Corynebacterium diphtheriae

Answer 11

throat, nasopharynx (respiratory tract), occasionally the skin

Respiratory Diphtheria: Typically localized to the throat and nasopharynx, characterized by the formation of a grayish pseudomembrane.

Cutaneous Diphtheria: Localized to the skin, presenting as chronic, with a grayish membrane.

Toxin Spread:
Systemic Toxicity: The diphtheria toxin can spread from the site of infection through the bloodstream to other organs. This can lead to complications such as myocarditis (inflammation of the heart muscle) and neuropathy (nerve damage), which are systemic effects of the toxin (severe).

Question 12

Medications for Corynebacterium diphtheriae

Answer 12

Erythromycin = Macrolides = 50S = Bacteriostatic
Penicillin G = intramuscular injection = Natural pen’s = inhibits the cross linking of PG’s = B-lactams

Question 13

Propionibacterium
-gram +/-
-shape
-w/ or w/o O2
-distinct feature

Answer 13

-gram (+)
-rod
-anaerobic
-part of the normal skin flora (acne development by producing sebum using lipases) and an early colonizer of dental plaque (propionic acid is a major by product of carbohydrate fermentation)

Question 14

Pathogenesis of Propionibacterium

Answer 14

-opportunistic pathogen
-Acne’s, CNS infections, endocarditis
-induce IL-1, and TNF
-isolated from root canal lesions w/ and w/o periapical abscesses

PART OF YOUR NORMAL SKIN FLORA AND DENTAL PLAQUE EARLY COLONIZER

Question 15

This bacterium is commonly associated with acne vulgaris and is also found in root canal infections and may present with periapical abscesses.

Answer 15

Propionibacterium

It is a Gram-positive, anaerobic rod that can contribute to both skin conditions and endodontic infections

Question 16

Clostridium tetani is known for causing a specific type of infection. Which condition is primarily associated with this bacterium, and how does it affect the body?

Answer 16

Clostridium tetani causes tetanus. The bacterium produces a potent neurotoxin that interferes with nerve signaling, leading to muscle rigidity and spasms. The toxin affects the motor neurons,
causing symptoms such as lockjaw, muscle contractions, and potential respiratory failure.

Question 17

Clostridium tetani is known for causing a specific type of infection. Which condition is primarily associated with this bacterium, and how does it affect the body?

Answer 17

Clostridium tetani causes tetanus. The bacterium produces a potent neurotoxin that interferes with nerve signaling, leading to muscle rigidity and spasms. The toxin affects the motor neurons, causing symptoms such as lockjaw, muscle contractions, and potential respiratory failure.

Question 18

Which Clostridium species is primarily known for causing botulism, and what is the primary mechanism of action of its toxin?

Answer 18

Clostridium botulinum is known for causing botulism. The primary mechanism of action of its toxin is the inhibition of acetylcholine release at neuromuscular junctions, leading to muscle paralysis and potentially respiratory failure.

Question 19

Which clostridium is classified by the CDC as category A agent since it is one of the deadliest toxins known

Answer 19

C.botulinum

Question 20

Clostridium species can be found in many environments. Where are these bacteria most commonly found in nature, and how might they enter the human body to cause infection?

Answer 20

Clostridium species are commonly found in soil, dust, water, and the intestines of humans and animals. They can enter the human body through wounds (as with C. tetani) or through ingestion of contaminated food (as with C. botulinum or C. perfringens). In the case of C. difficile, it often proliferates after disruption of normal gut flora, such as after antibiotic use.

Question 21

Clostridium
-gram +/-
-Shape
-w/ or w/o O2
-distinct feature

Answer 21

-gram (+)
-rod
-obligate anaerobes
-ENDOSPORES = ENDOSPORE!!!! Spore- forming bacteria which are highly resistant to environmental conditions such as heat, radiation, and chemicals.
+ EXOTOXINS

Exotoxins
-tetanus toxin
-Botulinum toxin

Question 22

Clinical classification of tetanus
-localized vs. Cephalic

Answer 22

-localized = muscle rigidity limited to the site of spore inoculation
-cephalic = form of localized Tetanus affecting cranial nerves, often following a head injury

Question 23

A patient who has not received routine vaccinations presents with trismus (lockjaw) and generalized muscle spasms. The infection is linked to a recent injury involving a contaminated object. Which bacterium is responsible for this presentation, and what toxin does it produce?

Answer 23

Clostridium tetani, producing tetanospasmin toxin.

Question 24

A patient presents with symptoms of muscle weakness, drooping eyelids, and difficulty swallowing after consuming home-canned food. The patient’s history and symptoms suggest a foodborne illness. What bacterium is most likely responsible for these symptoms, and what is the name of the toxin it produces?

Answer 24

C. Botulinum

Question 25

Porphyromonas Gingivalis is primarily what type of pathogen

Answer 25

Periodontal pathogen
-Chronic periodontitis
-Aggressive periodontitis

Question 26

In the context of periodontal disease, Porphyromonas gingivalis is often identified as a key pathogen. Which specific type of bacteria does Porphyromonas gingivalis primarily belong to, and what is its role in the progression of periodontal disease?

Answer 26

Porphyromonas gingivalis is a Gram-negative, anaerobic rod.

It plays a critical role in the progression of periodontal disease by contributing to the subgingival biofilm, causing inflammation b/c LPS stimulate IL-1

late colonizer in dental plaque

Question 27

What type of dental plaque colonizer is Porphyromonas Gingivalis?

Answer 27

Late colonizer

subgingival as well

Question 28

Tannerella forsythia
-gram +/-
-shape
-w/ or w/o O2
-found in what environments

Answer 28

Gram (-)
Rod
Anaerobic like Porphyromonas gingivalis
Found in subgingival and supragingival

Late colonizer
Endotoxin - LPS

Question 29

Which are late colonizers of the dental plaque

Answer 29

-Porphyromonas gingivalis
-Tannerella forsythia
-Prevotella intermedia

these 3 are also Periodontal pathogens