Prokaryotic cell structure and function Flashcards
Percentage of peptidoglycan in gram positive bacteria
90%
Percentage of peptidoglycan in gram negative bacteria
10%
In peptidoglycan, what bond links the NAM and NAG?
beta 1-4 glycosidic bond
NAM
amino sugar N-acetyl-muramic acid
NAG
amino sugar N-acetyl-glucosamine
Pentapeptide order in bacterial peptidoglycan
L-ala D-glu L-lys/DAP D-ala (D-ala)
Gram positive L-lys/DAP?
L-lys
Gram negative L-lys/DAP?
DAP
Do gram negative or gram positive peptidoglycan have a pentaglycine bridge?
gram POSITIVE
Pentapeptide order in archaeal pseudomurein
L-glu
L-ala
L-lys
L-glu———-L-lys
lipolysachharide (3 components)
O-specific polysaccharide
Core polysaccharide
Lipid A
In pseudomurein, what bond links the NAT and NAG?
beta 1-3 glycosidic bond
NAT
amino sugar N-acetyl-talosaminuronic acid
peptidoglycan monomer
two amino sugars (NAM and NAG)
with a pentapeptide extending off of NAM
What is slime capsule made of
polysaccharide, peptidoglycan or both
Fimbriae
long filamentous protein structures on the surface of bacteria that help them to bind to specific receptors
Hami (hamus)
long helical tube on surface of archaea that ahs three hooks at the far end to help adhere to otehr archaea or surfaces
Polyhydroxybutarates (PHBs)
macromolecules synthesised by bacteria which act as inclusion bodies and store reserve materials that bacteria can use under stress
Polyphosphate
linear polymers of phosphate units that provide energy store
Magnetosomes
membranous structures found in magnetotactic bacteria which contain iron rich magnetic particles that allow detection of the earths magnetic pole
(allows marine bacteria to move downwards to lower oxygen concentrations)
Gas vacuoles
allow bacteria to adjust density and move up/down water columns
4 rings in flagellum
L
P
MS
C
Endoflagellum
flagellum specific to most spirochaetes that forms axial filaments which rotate and propel the spirochaete in a twisting motion
Archaellum
Archaea version of a flagella which is half the width of a flagellum and uses ATP rather than a proton gradient.
Chemotaxis
movement down a chemical gradient
How do bacteria move up a gradient towards an attractant?
Biased increase in run length for the direction towards the attractant and decrease in run length in any direction away from it.
Three types of bacterial locomotion
gliding
flagellae
spirochaetal
