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Flashcards in Test 2C Deck (17):
1

SAM

cosubstrate coenzyme

2

NAD+ function

electron Carrier -accepts electrons -cosubstrate

3

NADH function

electron carrier -accepts electrons -transfers two electrons -cosubstrate

4

FAD

prosthetic group -forms double bonds -has intermediate radical -oxidize reduce double bonds -Stronger Oxidizing agent than NAD+ **3 6 sided Rings!

5

FADH2

transfer 1 or 2 electrons -prosthetic group -can hold the proton while NADH cannot and carries a hydride

6

Fatty acids with double bonds and Tm, van der waals

double bond "kink" causes the fatty acid to behave like a much shorter tail. -the kink pushes other fatty acids away inhibiting the formation of van der waals interactions

7

Nucleosomes

Neutralize most the of the remaining negative charge of the DNA strand (NUCLEOSOMES)

8

Arginine Grooves in DNA

attract negatively charged DNA strands, wrap themselves around the histone

9

DNA

wraps around 1 and 3/4 times -involves 146 base pairs about the histone octamer -54 base pairs between histones 200 BP per histone unit

10

Triacylglycerol function

used for fat storage (energy storage), insulation

11

Hydrophobic Effect and Nitrogenous Bases

nitrogenous bases are relatively hydrophobic and orient themselves inward to avoid the external hydrophillic enviroment. -The guanine/cytosine pairing is more hydrophobic than the adenosine/thymine thus forms first and is more stable

12

DNA stability

Counterions -dilute the negative charge of the DNA strands allowing them to hybridize or anneal together -WITH OUT countering NO DOUBLE STRANDED DNA Results: the DNA strands are metastable -allows for replication with little expenditure of energy

13

How to determine concentration of DNA?

Absorbance @ 260 -A260=E260 b c -2 ssDNA absorbe more light due to a lack of BASE STACKING

A image thumb
14

Explain the difference in composition between A and B in

?

A image thumb
15

Explain the forces involved in hyperchromaticity

Base Stacking(least), H-bonding, MORE HYDROPHOBIC AFFECT

 

-increase temp/denature/melting to go to ssDNA

-decrease temp/renature/hybridizing to go to dsDNA

16

What are the two types of cofactors?

Essential Ions:

-ACTIVATOR IONS:Mg2+ (ATP), Ca2+ (phosphotases), Zn2+(zinc fingers)--loosely bound

-Transition Metals(d orbitals):Fe2+, Zn2+, Co2+---tightly bound with active sight

Coenzymes:

-cosubstrates:co-reactant donate/accept functional groups DOES NOT NEED TO BE REGENERATED. ATP, NAD, NAD/NADH, CoA-SH

-prosthetic groups:tightly bound, part of the active site of the enzyme. MUST BE REGENERATED FAD/FADH2/FMN, PLP

17

Mg2+

-neutralizes charge-charge repulsion

-creates a six sided ring

-makes a good nucleophilic center