Cell Bio 1 Flashcards
mass spectrometry
measure mass and determine
unknown chemicals –proteins
often first digested with trypsin
x-ray diffraction
uses crystals of purified proteins and destructuretermines up to tertiary
NMR spectroscopy
uses crystals of purified proteins and determines up to tertiary
Immunoprecipitation
purify proteins from cells, add antibody, secondary antibody linked to beads, incubate, spin down the beads and run out on a gel. This allows protein complexes to be pulled out. Can label proteins ahead of
time or use a Western blot to identify proteins of interest.
Immunohistochemistry/ immunofluorescence
(Antibody staining) to look at protein localization in cells – can also see if 2+ proteins co-localize to the same subcellular region of a cell (at “low” resolution).
FRAP
fluorescene recovery after photobleaching
optical technique to quantify 2d lateral diffusion useful in studying membrane diffusion and protein binding
Michaelis Constant
Km, the [S] (substrate concentration) at 1/2 V
Michaelis and Menten equation
V=Vmax [S]/[S] + Km
reciprocal is Lineweaver-Burk plot (lower is better on this plot)
competitive inhibitors
reversibly bind to active site and prevent substrate bindin
non competitive inhibitors
reversibly bind another site on enzyme and prevent substrate interaction
irreverisble inhibitors
covalently bind enzyme and prevent substrate interaction
ex: nerve gas, penicillin
enzyme post translational modification
covalent modifications, most common is phosphorylation
causes conformational changes and alters interactions between active site and substrate
allosteric enzyme modulation
non covalent interaction with another molecule
occurs outside of active site and causes conformational change in active site
light microscopy equation for resolving power
distance = 0.61 wavelength/ refractive index sin alpha
fluorescent light microscopy
light is reflected
FRET
fluorescent resonance energy transfer
determines how close together in a cell 2 molecules are or follows activation of enzyme in situ (original place)
laser scanning confocal microscopy
similar to fluorescent microscopy but uses lasers to light one color and one focal plane at a time
scanning electron microscopy
reveals specimen topography
transmission electron microscopy
very high res images but potential for artifacts
subcellular fractionation
method to study organelles
homogenize cells and centrifuge, transfer and centrifuge to separate out through layers
lysosomes
degrades cellular garbage and enzymes active only at pH 4.8
linked to Tay Sachs disease
peroxisomes
single membrane, site of degradation of farry acids and toxins and bad oxygen
linked to adrenoleukdystrophy
N-glycosidic linkage
attached to asparagine amino acid residue
O-glycosidic linkage
attached to oxygen on serine or threonne resides
glycoproteins and glycolipids
90% of cells carbohydrates linked to proteins and 10% linked to lipids
Blood A type
GalNac to galactose
Blood B type
galactose to galactose
Blood O type
backbone, a and b add on to with carbohydrates
nonionic detergent
a polar head group and nonpolar hydrocarbon chain
peripheral membrane proteins
do not enter lipid bilayer, located entirely outside on either side
attach via non covalent interactions with polar head groups or integral membrane proteins and dissociate by high salt
RBC spectrin is example
lipid anchored MP
proteins may be achored to membrane
covalent attachment to hydrocarbon fatty acid/lipid
covalent attachment to carbohydrates that are attached to phospholipid
can be dissociated by enzymes that dissociate inositol-containing phospholipids
single particle tracking
monitor protein movement by labeling antibody coated gold particles
energy of solute movement for charged molecules
ΔG =(1.4 Kcal/mole) log10[Ci]/[Co] +zFΔEm
patch clamping
used to study ion channels by microelectrodes and applying charge to patch of membrane
Na+/glucose co transport
2 Na+ move down concentration gradient an 1 glucose moves against, without sodium, glucose would not be able to exit lumen, GLUT transporter then sends into blood
dendrites
receive incoming info
cell body
nucleus, metabolic hub
axon
conducts outgoing impulses
node of ranvier
where action potential happens
terminal knob
transmits signal to next cell
myelin sheath
insulator, speeds conductance
phosphoglycerides
diaceylglycerides with small functional head group linked to glycerol backbone by phosphate ester bonds
sphingolipids
ceramines formed by attachment of spingosine to fatty acids - rigid
cholesterol
smaller and less amphipathic , only found in animals, carbon rings are flat and rigid
