Exam 2 Micro

Glycocalyx

Is a repeating polysaccharide unit, consisting of carbohydrates linked to protein that covers the cell membrane, providing protection. Can be a slime layer or a capsule

Bacterial capsule

Is a thick less porus polysaccaride-based layer that surrounds some bacterial cell adhearing to the cell wall.

Bacterial capsule Clinical relevance

Virulence factor (Affects the bacterias ability to cause disease) protects the cell from performing phagocytosis (Eating itself). It is used to subtype different strains, and is a component is all pneumococcal vaccines

Cytoplasm in prokaryotic cells

Is made of 80% water and contains proteins, lipids, carbohydrates, and inorganic ions

Structures within cytoplasm (prokaryotic)

Nucleiod, plasmids, ribosomes

Nucleiod

Contains 1 or more chromosome (circular dsDNA, essential information), NO mebrane/nuclear envelope (Hanging in cytoplasm)

Plasmids

1 or more plasmids. Non-essential, anti-biotic resistance and toxins tolerance, special enzymes. Small circular dsDNA molecules (5-100) genes/plasmids. DNA needs to be copped. Independent of chromosomes in location and replication. Tools in biotech, can be used to transfer genes to bacteria.

Bacterial Ribosome

The site of protein synthesis in prokaryotic cells. Translation makes protien, turns mRNA —> protein. 70s ribosomes

70s Ribosomes

rRNA piece = 235rRNA (found in a large unit). Azithromycin (Z-pack) binds to 235rRNA to prevent it from functioning (making protein). Is selectively toxic.

Both 80s Ribosomes and 70s Ribosomes

Have the same jobs in both parts, have large and small units that attach together to make a functioning ribosome for protein synthesis

Antibiotics targeting the bacterial ribosome are selectively toxic

True

Bacterial Endospores

Dormat, Protects DNA from Stress. Only a small part of bacteria make endospore. Switches from Vegetative state to endospore when cell undergoes stressors. Does not reproduce while in the endospore state. The cell returns to the vegetative state when conditions become favorable again.

Vegetative Cell

The active state of a cell. This is when a cell reproduces. Venerable to environmental stress and can transform into an endospore when conditions become unfavorable.

Dipicolinic acid

DNA in an endospore

Sporulation Cycle

Cell copies its genome and dives asynchronously —> smaller cell turns into endospore

Bacillus anthracis

A rod-shaped bacterium. Disease, cutaneous, gastrointestinal and respiratory anthrax, Anthrax toxin (Lethal toxin+endema toxin) causes severe illness in humans and animals. Symptoms, respiratory anthrax, breathing difficulties, shock, meningitis, high fever

Clostridium botulinum

A gram-positive. Disease, botulism. Secretes botulism toxin.

Clostridium tetani

Disease tetanus. Secretes, Tetanospasmin.

Botulism (Clostridium botulinum)

Rare in the U.S (200 cases/year), Obligate anaerobe (Only lives without oxygen) Gram + bacillus. Vegetative cells produce botulinum toxin (the most potent toxin that we know made by an organism). Endospores live in soill and sediment, will reproduce when in a safe environment, like in improper canning. Mainly consumed by ingesting contaminated food. Can cause paralysis. Germinates in large intestine

Infant Botulism

Infant consumes endospore via Honey. Infants lack a complex microbiome; endospore germinates and releases toxins into the gut, can cause paralysis

C. difficile (Clostridioides)

Gram + bacillus. Obligate anaerobe (Hates Oxygen), will germinate in large intestine. Exists as endospore on surface then turns into a vegetative cell once it reaches anaerobic colon (Large intestine)

Dysbiosis

Bad bacteria in colon, caused by C. diff

C. diff symptoms

Causes watery diarrhea and colitis. Pseudomebreous (Yellowish inflammation plaque on colon wall). Toxic Megacolon.

C.diff Infection (CDI)

Leading cause of health care associated infectious diarrhea. Antibiotics are most common therapy to treat. Recurring infection is common.

Fecal Microbial Transplantation

When healthy stool from a donor is transferred to the colon of a patient to restore healthy gut bacteria. Takes the good bacteria from stool to restore what was lost during antibiotic use. Con microbes from stool are unknown.

SER-109

Oral capsules with specific bacterial endospores, FDA approved in 2023. Is delivered via capsule compared to FMT that is delivered via colonoscopy, tube, enema, or oral capsules. Better because the endospores/microbes are known

The type of microbes in FMT are known?

False

Types of microbes in SER-109 are known

True

Eukaryotic Cell Surface Structures

Flagella, glycocalyx, cell wall, cell membrane, plasma membrane, cytoplasm, and ribosomes