Cell Motility and Structure (Chapter 2)

Epulopiscium fishelsoni

Exceeds 600 micrometers in length, related to Clostridium, found in surgeonfish gut with multiple genome copies.

Thiomargarita namibiensis

Sulfur-oxidizing chemolithotroph, about 750 micrometers in diameter.

Coccus (pl. cocci)

Spherical or ovoid prokaryotic cell morphology.

Bacillus (pl. bacilli)

Cylindrically-shaped prokaryotic cell morphology, also known as 'ROD'.

Spirilla

Prokaryotic cells with a curved or loose spiral shape.

Spirochetes

Prokaryotic cells tightly coiled in shape.

Budding & Appendaged

Prokaryotic cell extensions as long tubes or stalks.

Filamentous

Prokaryotic cells that are long, thin cells or chains of cells.

Long Chain (e.g., Streptococcus)

Prokaryotic cells arranged in a long chain.

3D Cubes (e.g., Sarcina)

Prokaryotic cells arranged in a 3D cube shape.

Grape-like clusters (e.g., Staphylococcus)

Prokaryotic cells clustered in a grape-like formation.

Surface-to-Volume Ratio

Ratio that controls properties like growth rate and evolution in cells, higher in small cells.

Haponoids

Sterol-like molecules strengthening cytoplasmic membranes of certain bacteria, 8-10 nm wide.

Sterols

Rigid and planar molecules strengthening eukaryotic cell membranes, often lacking a cell wall.

Integral Membrane Proteins

Proteins embedded in the cytoplasmic membrane of cells.

Peripheral Membrane Proteins

Loosely attached lipoproteins interacting with integral membrane proteins in cellular processes.

Phospholipids

Polar lipids with two fatty acids, a glycerol unit, and a phosphate group esterified to organic molecules.

Archaeal Membranes

Similar to bacterial membranes but with ether bonds, hydrophobic region from repeating isoprene units.

Transport Proteins

Accumulate solutes against concentration gradient, ensuring efficient biochemical reactions in cells.

Cytoplasm Nutrients

Ensures biochemical efficiency by maintaining adequate nutrient concentrations.

Phosphoglycerol Tetraethers

Archaeal lipids with high sensitivity and specificity.

Proton Motive Force

Charge separation creating membrane energy for various reactions.

Cell Lysis

Cell bursting due to internal pressure.

Peptidoglycan Polymer

Cross-linked strands forming a strong cell wall structure.

Glycan Tetrapeptide

Peptide with modified glucose residues and amino acids.

Lysozyme

Enzyme cleaving glycosidic bonds in peptidoglycan.

Pleomorphic

Shape-shifting cell lacking a cell wall.

Teichoic Acids

Acidic molecules binding metal ions in gram-positive bacteria.

Outer Membrane (LPS)

Second lipid bilayer in gram-negative bacteria, mostly polysaccharide.

Periplasm

Space between cytoplasmic and outer membrane, housing extracellular proteins.

Core Polysaccharide

Component of LPS with various sugars like heptoses and N-acetylglucosamine.

O-specific Polysaccharide

Connected to core polysaccharide, consists of galactose, glucose, rhamnose, and mannose.

Hydrolytic Enzymes

Degradation enzymes for polymeric substances in the periplasm.

Lipid A

Part of LPS with fatty acids linked to the core polysaccharide.

Chemoreceptors

Proteins governing chemotaxis response in bacteria.

Binding Proteins

Initiate substrate transport in bacterial cells.

Porins

Channels allowing solute entrance and exit, making the outer membrane permeable.

Braun Lipoprotein

Molecule that anchors the outer membrane to the peptidoglycan layer.

Specific Porins

Porins with a binding site for specific substances or groups of structurally related substances.

Nonspecific Porins

Porins that allow virtually any very small hydrophilic substance to pass through.

S-Layer

Paracrystalline surface layer composed of interlocking protein or glycoprotein molecules.

Pseudomurein

Peptidoglycan-equivalent of archaeal cell walls, formed from alternating repeats of N-acetylglucosamine and N-acetyltalosaminuronic acid.

Methanosarcina

Archaea with thick polysaccharide walls composed of polymers of glucose, glucuronic acid, galactosamine uronic acid, and acetate.

Halococcus

Extremely halophilic Archaea with cell walls containing large amounts of sulfate to stabilize the cell wall in high-salt environments.

Capsule

Organized matrix tightly attached to cells, visible by light microscopy when treated with India ink.

Slime Layer

Less organized layer loosely attached to cells, difficult to see microscopically.

Biofilm

Thick layer of cells where bacteria bind to solid surfaces, with polysaccharides playing a key role in development and maintenance.

Fimbriae

Thin filamentous protein structures enabling cell adhesion to surfaces or the formation of biofilms.

Pili

Longer filamentous protein structures than fimbriae, facilitating genetic exchange between cells and adhesion to specific host tissues.

Hami

Unique structure resembling a tiny grappling hook, key colonization factor for certain human pathogens.

Poly-beta-hydroxybutyric acid (PHB)

Lipid polymer serving as a reserve carbon and energy source in cells.

Polyphosphates

Polymers of PO4 serving as reserves of phosphate and possibly high-energy phosphate.

Sulfur Globules

Reserve energy and/or electrons in the form of elemental sulfur.

Magnetosomes

Protein shells inflated with magnetic iron oxide, providing orientation in a magnetic field.

PHA

Synthesized by cells in carbon excess, used as carbon or energy sources.

Polyphosphate

Granules formed in phosphate excess, source for nucleic acid and phospholipid biosynthesis.

Sulfur Bacteria

Gram-negative Bacteria and Archaea oxidizing reduced sulfur compounds.

Glycogen

Glucose polymer.

Gas Vesicles

Structures providing buoyancy to cells in water columns.

Endospores

Heat-resistant, light-refractive structures allowing dormancy and rapid conversion.

Cutaneous Anthrax

95% of naturally occurring anthrax, causing painless black ulcers.

Exosporium

Thin protein covering of endospores.

Sporulation

Cellular differentiation process from vegetative growth to endospore formation.

Gas Vesicle Structure

Hollow, rigid, conical-shaped structures aiding in buoyancy.

Dipicolinic Acid

Accumulates in endospore core, complexes with Ca2+.

SASPs

Small acid-soluble spore proteins protecting DNA in endospores.

Core

Contains core wall, cytoplasmic membrane, nucleoid, ribosomes, and essentials.

Spore Coat

Layers of spore-specific proteins in endospores.

LOPHOTRICHOUS FLAGELLATION

polar flagellation where a tuft arises at one end of the cells.

AMPHITRICHOUS FLAGELLATION

when a tuft of flagella emerges from both poles of the cell

PERITRICHOUS FLAGELLATION

flagella are inserted around the cell surface

FLAGELLUM

make bacteria motile by swimming, analogous to the structure archaellum

TUFT

a group of flagella

FILAMENT

main part of the flagellum, composed of many copies of a protein called flagellin

ROTOR

consists of the central rod and the L, P, C, and MS rings; collectively, these make up the BASAL BODY

STATOR

consists of the Mot protein that surround the rotor and function to generate torque

CHEMOTAXIS

a response to chemicals

PHOTOTAXIS

a response to light

RUNS

when cells move in a random fashion, in which the cell is swimming forward