Introduction to Microbiology and Microbial Genetics

Vocabulary flashcards covering the foundations of microbiology, historical figures, microbial classification, and the molecular mechanisms of DNA replication, transcription, and translation.

Microorganism

Any organism that cannot be seen by the naked eye.

Dr. Carl Woese

The scientist who defined the three domains of life based on the sequences of the 16s portion of ribosomal RNA of organisms.

Archaea

A domain of prokaryotic organisms with cell walls lacking peptidoglycan and membrane lipids composed of branched carbon chains attached to glycerol by ether linkage.

Bacteria

A domain of prokaryotic organisms with cell walls containing peptidoglycan and membrane lipids composed of straight carbon chains attached to glycerol by ester linkage.

Prions

Noncellular infectious proteins described as the smallest infectious agents.

Binomial nomenclature

A system of scientific naming that assigns two names (genus and specific epithet) to each organism.

Strain designation

An additional classification for prokaryotes, such as Escherichia coli O157:H7, where O represents the O antigen and H represents the fimbrial antigen.

Robert Hooke

Observed "cells" in cork tissue in 1665 using an improved microscope, leading to the development of Cell Theory.

Antoni van Leeuwenhoek

Observed "animalcules" in rainwater and materials scraped from his teeth between 1673 and 1723.

Lazzaro Spallanzani

Carried out experiments in 1765 showing that boiling and sealing broth prevented microbial growth, helping to refute the hypothesis of spontaneous generation.

Ignaz Semmelweis

Demonstrated in the 1840s that hand washing with chlorinated lime solutions prevented childbed fever.

Louis Pasteur

Used swan neck flasks in 1861 to prove microbes are present on nonliving matter and can be destroyed by heat, forming the basis for aseptic technique.

Joseph Lister

The "Father of modern surgery" who used phenol on wounds in the 1860s to reduce infection.

Koch's postulates

A series of four conditions established by Robert Koch in 1876 to prove that a specific microbe causes a specific infectious disease.

Angelina Hesse

Determined that agar could be used to prepare solid media, allowing for the isolation of bacteria like Mycobacterium tuberculosis in pure culture.

Edward Jenner

Developed the first vaccine in 1796 by infecting people with cowpox to protect them from smallpox.

Paul Ehrlich

Discovered salvarsan in 1910, an arsenic derivative used for the treatment of syphilis and the first chemotherapeutic drug against bacterial infections.

Alexander Fleming

Discovered penicillin, the first antibiotic, in 1929 after observing mold contamination on bacterial plates.

Plasmids

Small, usually circular segments of extrachromosomal DNA found in cells.

DNA gyrase

An enzyme that introduces negative supercoils into bacterial DNA and is the target for quinolone antibiotics like ciprofloxacin.

Central Dogma of Molecular Biology

The framework describing the flow of genetic information: DNA $\rightarrow$ RNA $\rightarrow$ Protein.

Mutation rates

Rates estimated at 1 in $10^{10}$ bases incorporated during DNA replication; they are important for understanding how organisms change in response to the environment and develop antibiotic resistance.

Polycistronic

A characteristic of prokaryotic transcribed RNA where multiple genes are regulated by a single promoter, allowing multiple proteins to be produced in a chain.

Monocistronic

A characteristic of eukaryotic transcribed RNA where a single gene is placed on a single promoter.

Degenerate code

A property of the genetic code where 61 sense codons exist for only 20 amino acids.

Anticodon

The complementary sequence on tRNA that pairs with a codon on mRNA to determine which amino acid is brought to the ribosome.

Prokaryotic Ribosome

A 70S ribosome composed of 30S and 50S subunits.

Eukaryotic Ribosome

An 80S ribosome composed of 40S and 60S subunits.

Aseptic technique

Procedures designed to prevent contamination by unwanted microbes, based on the discovery that microbes are present on nonliving matter and can be killed by heat.

Transcription-coupled translation

A process occurring in the cytoplasm of prokaryotic cells where transcription and translation take place simultaneously.