External Components and Motility

MGI 301

glycocalyx

polysaccharide that forms capsule and slime layers

hook

flexible curved protein that connects the filament of a flagellum to the basal body

capsule

semi-rigid, tightly bound glycocalyx that protects the cell from dehydration, starvation, and phagocytosis

polar/monotrichous

one flagellum on one end of the bacteria cell

removal of moisture

desiccation

fimbriae

short, hair like protein filaments that coat the surface of some bacteria, allows bacteria to adhere to hosts cells, surfaces, and each other because of proteins called adhesions

flagella

helical, hollow protein appendages that rotate to provide motility

tumble

when flagellum stop corkscrew motion to reorient/reverse direction

filament

the outermost, long, and hollow component of a flagellum made of flagellin protein

forward run

when flagellum rotate in a corkscrew motion to move the cell in a single direction

mot proteins (stator)

proteins in the basal body that convert proton motive force (PMF) into rotation

pili

protein tubes that function in adhesion, motility, and genetic exchange (conjunction); long, delicate, and few in number

india ink

stains the background of a smear making cells appear colorless on a dark background (negative simple stain)

rings (rotor)

rotating component of flagellar motor

aggregation/flocculation

ability of microbes to adhere/stick to each other

adhesins

proteins attached to fimbriae that allow for specific binding of bacteria to a certain host cell type

basal body

membrane bound part of flagellum, made up of mot proteins and ring proteins, the motor

lophotrichous

numerous flagella located at one end of a bacterial cell

conjugative pili

protein tube that allows for DNA exchange between two gram-negative bacteria

host specificity

binding of a microbe to target hosts, determines host range

slime layer

non-rigid, loosely bound glycocalyx, protects from dehydration and starvation

tissue tropism

binding of bacteria to a specific tissue type

peritrichous

numerous flagella are located all around the bacteria cell