Exam 4- Microbiology

catabolism

Metabolic pathways that break down molecules, releasing energy.

anabolism

Metabolic pathways that construct (build) molecules, requiring energy.

simple enzymes

biological catalysts, that speed up chemical reactions in living organisms

conjugated enzymes

complex protein that consists of a protein part (apoenzyme) and a non-protein part (cofactor

haloenzymes

active compound formed by the combination of an enzyme with a coenzyme.

cofactors

a non-protein substance that is required for the function of an enzyme or protein

apoenzymes

the protein portion of an enzyme that requires a cofactor to become active

coenzymes

an organic molecule that assists enzymes in catalyzing biochemical reactions

active site

a region on an enzyme that binds to a protein or other substrate during a reaction.

constitutive enzyme

an enzyme that is produced continuously at a constant rate and level, regardless of the metabolic state of the cell or the presence or absence of a specific substrate

regulated enzymes

an enzyme whose activity is controlled or modulated by external factors or internal cellular conditions, rather than being constitutively active

competitive inhibition

a type of enzyme inhibition where an inhibitor molecule binds to the active site of an enzyme, competing with the substrate for binding

noncompetitive inhibition

a type of enzyme inhibition where an inhibitor molecule binds to an enzyme at a site other than the active site, preventing the enzyme from functioning properly

enzyme repression

the mechanism by which the synthesis of an enzyme is reduced or blocked by specific molecules, often the end products of the metabolic pathway it catalyzes

enzyme induction

the process where a microbial cell increases the production of a specific enzyme in response to a specific chemical signal or environmental factor

exergonic reaction

a spontaneous chemical reaction that releases energy, resulting in a negative change in free energy

endergonic reaction

a type of chemical reaction that absorbs energy from its surroundings to proceed

oxidation-reduction reaction (redox)

type of chemical reaction that involves a transfer of electrons between two species.

glycolysis

a metabolic pathway where glucose is broken down into pyruvate, producing energy (ATP) and reducing equivalents (NADH)

krebs cycle

second stage of cellular respiration, in which pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions

electron transport chain

series of electron carrier proteins that shuttle high-energy electrons during ATP-generating reactions

aerobic respiration

a cellular process where organisms break down nutrients in the presence of oxygen to produce energy in the form of ATP

-final electron acceptor: oxygen

fermentation

a metabolic process where microorganisms like bacteria and yeast break down organic compounds, such as glucose, in the absence of oxygen, to produce energy (ATP) and various byproducts like alcohol, lactic acid, or carbon dioxide. It's a key part of anaerobic respiration, allowing organisms to generate

anaerobic respiration

a cellular respiration process that occurs in the absence of oxygen, using alternative electron acceptors to generate ATP

-final electron acceptor: inorganic molecule (nitrate, sulfate, or carbon dioxide)

sterilization

a process of complete elimination or destruction of all forms of microbial life (i.e., both vegetative and spore forms), which is carried out by various physical and chemical methods.

disinfection

the process of eliminating or reducing the number of harmful microorganisms on inanimate objects, such as surfaces, equipment, or surgical instruments

decontamination

the process of removing or inactivating harmful microorganisms from surfaces, objects, or environments

antisepsis

the process of preventing or inhibiting the growth and multiplication of microorganisms on living tissues

bactericidal

the ability of an agent to kill bacteria

bacteristatic

an antimicrobial agent that inhibits the growth or reproduction of bacteria, but does not necessarily kill them outright

sepsis

a systemic illness caused by microbial invasion of normally sterile parts of the body, leading to a dysregulated host response and potential organ dysfunction

asepsis

the state of being free from harmful microorganisms

antiseptics

substances that inhibit or kill microorganisms on living tissues, such as the skin or mucous membranes

mode (mechanism) of action

the specific way in which a substance, like a drug or antimicrobial agent, affects living organisms at a cellular level

pasteurization

a heat treatment process used to kill harmful pathogens in food and beverages without significantly altering their chemical composition or nutritional value

lyophilization

a preservation technique used in microbiology and other fields that involves rapidly freezing a substance, then subjecting it to a vacuum, allowing the frozen water (ice) to directly transform into vapor (sublimate) without melting

heat

using temperature to either kill or inhibit the growth of microorganisms. This can be achieved through high temperatures (like autoclaving, boiling, or incinerating) or low temperatures (like refrigeration or freezing)

radiation

uses energy emitted from atomic activities to damage or kill microorganisms by altering their DNA or cellular structures

filtration

utilizes a porous barrier to separate and remove microorganisms from liquids or air

osmotic pressure

involves creating a hypertonic (high solute) environment, which causes water to be drawn out of microbial cells, inhibiting growth and potentially killing them

genomes

the complete set of genetic material, DNA or RNA, within an organism, including all genes and non-coding sequences

structural genes

a DNA sequence that codes for the amino acid sequence of a protein, such as an enzyme, or for a ribosomal RNA or transfer RNA molecule

genotype

genetic makeup of an organism

phenotype

An organism's physical appearance, or visible traits.

nucleotide

the basic building block of nucleic acids (RNA and DNA)

purines

a class of nitrogen-containing heterocycles that are vital components of nucleic acids and play a role in various cellular processes

pyrimidines

one of two types of nitrogenous bases that are essential components of nucleic acids

antiparallel arrangement

the two strands of a DNA molecule run in opposite directions.

DNA replication

the process where a cell creates an identical copy of its DNA before dividing, ensuring each daughter cell receives a complete copy of the genetic material

semiconservative replication

the process where each new DNA molecule is formed by using one original strand and one newly synthesized strand

-half old DNA and half new DNA

function of DNA polymerase III

-primary enzyme responsible for DNA replication in prokaryotes.

-It synthesizes new DNA strands, using the existing DNA strand as a template.

function of the topoisomerases

involved in chromosome segregation and decatenation (unlinking of intertwined DNA molecules) during replication and recombination.

function of the helicases

unwinds double-stranded DNA or RNA molecules into single strands

transcription

process where DNA is used as a template to create an RNA molecule

translation

the process by which messenger RNA (mRNA) is decoded to synthesize a protein

central theme of biology

-information flows from DNA to RNA to protein

-evolution

RNA

single-stranded, uses the sugar ribose, and contains the base uracil instead of thymine.

DNA

the molecule that carries the genetic instructions used in the development and functioning of all known living organisms

Messenger RNA

RNA molecule that carries copies of instructions for the assembly of amino acids into proteins from DNA to the rest of the cell

transport RNA

carries specific amino acids to the ribosome to be added to the growing polypeptide chain.

ribosomal RNA

cellular machinery responsible for protein synthesis, translating genetic information from messenger RNA (mRNA) into specific protein sequences

regulatory RNA

non-coding RNA molecules that control gene expression in bacteria

primer RNA

a short, single-stranded RNA sequence that initiates DNA synthesis. It provides a starting point for DNA polymerase to begin adding nucleotides to create a new DNA strand

ribozymes

a ribonucleic acid (RNA) molecule with the ability to catalyze biochemical reactions, similar to the action of protein enzymes

codons

a sequence of three consecutive nucleotides in DNA or RNA that specifies a particular amino acid or signals the start or stop of protein synthesis

polyribosomal complex

a structure formed by multiple ribosomes attached to a single mRNA molecule

eukaroytic transcription

the process by which the genetic information in a eukaryotic cell's DNA is copied into RNA molecules, specifically mRNA, tRNA, and rRNA.

-involves three polymerases

eukaryotic translation

the process by which eukaryotic cells use messenger RNA (mRNA) to produce proteins

bacterial transcription

process where bacterial DNA is copied into RNA by an enzyme called RNA polymerase

bacterial translation

conversion of mRNA into proteins within bacteria

introns

non-coding DNA sequences within a gene that are transcribed into RNA but are removed before the RNA is translated into a protein

exons

coding sections of an RNA transcript, or the DNA encoding it, that are translated into protein

operons

a unit of gene expression in prokaryotes (like bacteria) where a cluster of genes, along with their regulatory sequences, are transcribed together as a single mRNA molecule, often encoding functionally related proteins

F factor

plasmid that allows bacteria to undergo conjugation

resistance plasmids

extrachromosomal DNA molecules (small, circular pieces of DNA) that carry genes conferring resistance to one or more antibiotics, heavy metals, or other environmental toxins

transposons

a segment of (DNA) with the ability to move from one genetic location to another

wild strain

represents the typical, natural form of a species, as it exists in its natural environment

mutant strain

an organism that has a heritable change in its genetic material, resulting in a phenotype that differs from the wild-type strain

restriction endonucleases

proteins that cut DNA at specific sequences, acting as a defense mechanism in bacteria against invading viruses

clones

a number of different processes that can be used to produce genetically identical copies of a biological entity

vectors

an organism that transmits infectious agents, like pathogens, from one organism to another, often without being infected itself

recombinant DNA technology

the process of manipulating DNA outside of a living organism, specifically by joining DNA fragments from different sources to create new genetic combinations

Spontaneous mutations

changes in an organism's DNA that occur naturally, without any external influence or intervention

Induced mutations

changes in an organism's DNA that are deliberately caused by exposure to external agents, known as mutagens

Point Mutations

a genetic mutation where a single nucleotide base is changed, inserted or deleted from a DNA or RNA sequence of an organism's genome

Neutral Mutations

a genetic change that does not significantly affect an organism's ability to survive or reproduce

Missense Mutation

type of point mutation where a single nucleotide change in the DNA sequence results in a different amino acid being incorporated into the protein

nonsense mutation

a genetic change that introduces a premature stop codon into a protein-coding sequence, leading to a truncated or nonfunctional protein

silent mutation

a type of substitution, or point, mutation, wherein the change in the DNA sequence of the gene has no effect on the amino acid sequence

back-mutation

a change in a gene that restores it to its original, wild-type state

conjugation

a form of horizontal gene transfer in bacteria where genetic material, often in the form of a plasmid, is transferred from a donor cell to a recipient cell through direct cell-to-cell contact

transformation

type of horizontal gene transfer involves bacteria taking up DNA from their environment

transduction

mechanism of horizontal gene transfer (HGT) where a virus (bacteriophage) transfers DNA from one bacterial cell to another.