Chapter 8: Microbial Biology Flashcards
Biochemistry
The discipline that studies the chemistry of life, and its objective is to explain form and function based on chemical principles.
Organic Chemistry
The discipline devoted to the study of carbon-based chemistry, which is the foundation for the study of biomolecules and the discipline of biochemistry.
Macronutrients
Hydrogen, carbon, oxygen, nitrogen, phosphorus, and sulfur; they account for about 99% of the dry weight of cells.
Micronutrients/ Trace Elements
Elements required by some cells in very small amounts like sodium, potassium, magnesium, zinc, iron, calcium, molybdenum, copper, cobalt, manganese, or vanadium.
Inorganic Compounds
Compounds that do not contain carbon.
Organic Molecules
Typically organized around chains of carbon atoms.
Biomolecules
A molecule that is produced by a living organism.
Carbon Skeleton
Carbon atoms binding together in large numbers.
Macromolecule
A molecule containing a very large number of atoms, such as a protein, nucleic acid, or synthetic polymer.
Monomer
A molecule that can be bonded to other identical molecules to form a polymer.
Polymer
A substance that has a molecular structure consisting chiefly or entirely of a large number of similar units bonded together.
Dehydration Synthesis
Monomer molecules bind end to end in a process that results in the formation of water molecules as a byproduct.
Starch
Branched polymer, the primary energy storage molecule in plants.
Glycogen
Branched polymer; the primary energy-storage molecule in animals and bacteria.
Cellulose
Consists of a linear chain of glucose molecules and is a common structural component of cell walls in plants and other organisms.
Glycosidic Bonds
How the monomeric units of polysaccharides are linked together.
Polysaccharides (Glycans)
Large polymers composed of hundreds of monosaccharide monomers, they are not sweet and, in general, they are not soluble in water.
Ergosterol
Produced by fungi, and some protozoa, which strengthens the cell membranes of these organisms.
Hopanoids
Produced by bacteria, are multi-ringed structures that strengthen bacterial membranes.
Cholesterol
Consists of four rings with a double bond in one of the rings, and a hydroxyl group at the sterol-defining position, its function is to strengthen cell membranes in eukaryotes and in bacteria without cell walls.
Aresteols
The most common type of steroid containing an OH group, mainly hydrophobic molecules, but also have hydrophilic hydroxl groups.
Steroids
A complex, ringed structures that are found in cell membranes, some function as horomones.
Isoprenoids/Terpenoids
Branched lipids, formed by chemical modifications of the isoprene molecule.
Lipid-Bilayer/ Unit Membranes
Large, two-dimensional assemblies of phospholipids congregated tail to tail.
Micelles
Spherical assemblies containing a hydrophobic interior of phospholipids tails and an outer surface of polar head groups.
Amphipathic
A molecule presenting a hydrophobic portion and a hydrophobic moiety.
Triacylglycerol/Triglyceride
Formed when three fatty acids are chemically linked to a glycerol molecule, the primary components of adipose tissue, and are major components of sebum.
Unsaturated Fatty Acids
Fatty acids with hydrogen chains containing at least one double bond which causes kinks in their carbon skeleton.
Saturated Fatty Acids
Fatty acids with hydrocarbon chains that contain only single bonds, they have the greatest number of hydrogen atoms possible and are, therefore, “saturated” with hydrogen.
Fatty Acids
Lipids that contain long-chain hydrocarbons terminated with a carboxylic acid functional group.
Lipoprotein
A conjugate protein that has a lipid attached.
Glycoprotein
A conjugated protein that has a carbohydrate attached.
Conjugated Proteins
Have a nonprotein portion.
Quaternary Structure
Stabilized by relatively weak interactions.
Polypeptides/Protein Subunits
These proteins function adequately only when all subunits are present and appropriately configured.
Denatured
Implies the loss of the secondary structure and tertiary structure (and, if present, the quaternary structure) without the loss of the primary structure.
Native Structure
Folded proteins that are fully functional in their normal biological roles.
Disulfide Bridges
Bonds between the sulfhydrl (-SH) functional groups on amino acid side groups; hydrogen bonds; ionic bonds; and hydrophobic interactions between nonpolar side chains.
Tertiary Structure
The large-scale three-dimensional shape of a single polypeptide chain, determined by interactions between amino acids residues that are far apart in the chain.
Beta-Plated Sheet
The pleats are formed by similar hydrogen bonds between continuous sequences of carbonyl and amino groups that are further separated on the backbone of the polypeptide chain.
Alpha-Helix
The helix is held by hydrogen bonds between the oxygen atom in a carbonyl group of one amino acid and the hydrogen atom of the amino group that is just four amino acid units farther along the chain.
Secondary Structure
When hydrogen bonding occurs between amine and carbonly functional groups within the peptide backbone, resulting in localized folding of the polypeptide chain into helices and sheets.
Primary Structure
The sequence of amino acids that make up the polypeptide chain.
MALDI-TOF
Identifies microorganisms by determining the specimen’s mass spectrum and then comparing it to a database that contains known mass spectra for thousands of microorganisms.
FAME Analysis
Fatty acids are extracted from the membranes of microorganisms, chemically altered to form volatile methyl esters, and analyzed by gas chromatography.
PLFA Analysis
Phospholipids that have released their fatty acids are subjected to FAME analysis.
