BIOS5480 Microbial World Flashcards

Flashcards covering key vocabulary related to microbial cell structure, function, specialized structures, microbial ecology, and symbioses.

Bacillus

Rod-shaped prokaryotic cell.

Coccus

Spherical-shaped prokaryotic cell.

Spirillum

Spiral-shaped prokaryotic cell.

Spirochete

Corkscrew-shaped prokaryotic cell.

Streptococci

Chain of cocci-shaped bacteria (e.g., Streptococcus pyogenes).

Diplococci

Pair of cocci-shaped bacteria (e.g., Streptococcus pneumoniae).

Vibrios

Comma-shaped bacteria (e.g., Vibrio cholerae).

Spirilla

Thick, rigid spiral-shaped bacteria (e.g., Helicobacter pylori).

Spirochaetes

Thin, flexible spiral-shaped bacteria (e.g., Treponema pallidum).

Staphylococci

Cluster of cocci-shaped bacteria (e.g., Staphylococcus aureus).

Epulopiscium fishelsoni

A large heterotrophic bacteria, relative of Clostridium spp. and symbiont of surgeonfish, initially mistaken as a Protist.

Teichoic acid

Wall-associated protein found in Gram-positive cell walls.

Lipoteichoic acid

Anchors the peptidoglycan layer to the cytoplasmic membrane in Gram + bacteria.

LPS (Lipopolysaccharide)

Greatest variation in O-specific component found in Gram-negative cell walls.

Porin

Protein forming pores in the outer membrane of Gram-negative bacteria; composed of 3 proteins and 4 pores.

Pseudomurein

Archaeal cell wall component; differing from peptidoglycan in sugar composition and linkages.

Pili (Fimbriae)

Hair-like appendages on bacterial cells used for attachment.

Twitching motility

A type of surface movement mediated by Type IV Pili.

PHB (Polyhydroxybutyrate)

Type of cell inclusion in bacteria used for carbon storage.

Magnetosomes

Intracellular structures containing magnetic crystals (e.g., Magnetospirillum magnetotacticum).

Dipicolinic acid (DPA)

A chemical compound which comprises 5% to 15% of the dry weight of bacterial spores; implicated in heat resistance.

Gas vesicles

Intracellular structures that regulate buoyancy in planktonic cyanobacteria.

GvpA and GvpC

Key proteins in gas vesicle structure; GvpA forms a rigid β-sheet, and GvpC forms an α-helix.

Peritrichous

Flagella arrangement where flagella are distributed over the entire cell surface.

Polar

Flagella arrangement where the flagella are located at one or both poles of the cell.

Lophotrichous

Flagella arrangement where there are multiple flagella at one pole of the cell (flagella tufts).

Flagellin

The major protein component of flagella, recognized by plant and animal immune systems.

TLR5, NLRC4, FLS2

Receptors involved in innate immune recognition of flagellin.

Assimilation

Process by which organisms acquire an element to build into cells.

Dissimilation

Process of breaking down organic nutrients to inorganic minerals.

Biomass

Bodies of living organisms.

Trophic levels

Levels of consumption in a food web.

Populations

Cells of a single species.

Guilds

Metabolically related organisms.

Communities

A community of organisms and their natural environment.

Symbiosis

The most intimate association between organisms of different species.

Mutualism

A symbiotic relationship where each partner species benefits from the other and may fail to grow independently.

Synergism

A symbiotic relationship where both species benefit through growth, but the partners are easily separated and can grow independently.

Commensalism

A symbiotic relationship where one species benefits, while the partner species neither benefits nor is harmed.

Amensalism

A symbiotic relationship where one species benefits by harming another; the relationship is nonspecific.

Parasitism

A symbiotic relationship where one species (the parasite) benefits at the expense of the other (the host). The relationship is usually obligatory for the parasite.

Syntrophy

A metabolic association requiring both partners to complete the metabolism with a ΔG < 0.

Rhizosphere

The region of soil outside the rhizoplane that receives substances from the root.

Mycorrhizae

Symbiotic associations between fungi and plant roots.

Ectomycorrhizae

Mycorrhizae that colonize the rhizoplane; fungal mycelia do not penetrate the root cells.

Endomycorrhizae

Mycorrhizae that form a more intimate association in which fungi penetrate plant cells.

Wetland

A region of land that undergoes seasonal fluctuations in water level, alternating between dry, oxygenated conditions and water-saturated, anaerobic conditions.

Endophytes

Bacteria or fungi that colonize the transport vessels of plants.

Rhizobium

Bacteria attracted to legumes by chemotaxis, ultimately differentiating into bacteroids within the plant.

Haustorium

A specialized structure produced by some fungal plant pathogens to acquire nutrients from plant cells.