Control of Microbial Growth and Antimicrobial Drugs Practice Flashcards

This set covers key definitions and concepts regarding the control of microbial growth and the mechanisms of antimicrobial drugs as outlined in the BIO 205 Exam 3 Study Guide.

Sterilization

The complete destruction or removal of ALL microbial life, including endospores.

Sanitization

The process of reducing microbes to a safe public-health level, though not all microbes are necessarily killed.

Effect of Heat on Proteins

Breaks weak bonds which denatures protein shape and destroys enzyme function.

Effect of Extreme pH on Proteins

Disrupts ionic bonds, leading to the denaturation of enzymes and structural proteins.

high salt environment

The result of a high salt (hypertonic) environment drawing water out of a cell, which disrupts protein folding.

Autoclaving

A sterilization mechanism using pressurized steam

Optimal Temperature

The specific temperature at which an organism grows fastest and best.

25 \mu m Mask Filter

A filter used to trap larger particles and droplets; it protects against coronavirus by blocking the larger respiratory droplets carrying the virus.

Thymine Dimers

Mutations formed in DNA after absorbing UV radiation, leading to cell death or cancer.

Endospores

The most bleach-resistant microbial structures due to their thick coat, dehydrated core, and dipicolinic acid.

Halogens

A group of chemical disinfectants including chlorine, iodine, bromine, and fluorine that oxidize and damage cells

Heavy Metals (Hg) Mechanism

Binding to ($-SH$) groups on proteins, which denatures enzymes.

Alexander Fleming

The individual who discovered Penicillin in $1928$.

Broad-spectrum Drug

An antimicrobial effective against both Gram-positive and Gram-negative bacteria, such as Tetracycline.

Narrow-spectrum Drug

An antimicrobial effective against a specific group of microbes, such as Penicillin which mainly targets Gram-positive bacteria.

Superinfection

A secondary infection, such as $C.\,diff$, that occurs when broad-spectrum drugs kill the normal microbiota.

Selective Toxicity

structures unique to bacteria such as peptoglycan and ribosomes

Polyenes

antifngal drug that bind to ergosterol in the fungal membrane; they have no effect on bacteria.

Echinocandins

Antifungal drugs that block fungal cell-wall ($\beta\text{-glucan}$) synthesis; they do not affect human cells or bacteria.

Flucytosine

An antifungal drug converted to toxic $5\text{-FU}$ by fungal cytosine deaminase; it is selectively toxic because humans lack this enzyme.

antibiotic resistance

causes spontaneous mutations, horizontal gene transfer, enzymatic inactivation and biofilms

gram positive specific drug

targets exposed thick peptoglycan