46-47

base pairs that make imino

what mutation do they make?
Cytosine and Adenime ( have amino groups) - CA!
- they cause transition mutation ( change purine for purin and pyrimidine for pyrimidine)
- C behaves like T (so imino form of C will complement base pair with A) , A behaves like G
base pairs that make enol

what do they behave like?

G and T

the also cause transition mutation
base analogue of thymine

more common than what form of thymine?

B-bromouracil

more common than the enol form of thymine
this test use back mutation.

used to find out the % if carcinogens that are also mutagens (what %?)

Ames test, 80%
simplest alkylating agent

DMS (dimethyl sulphate)
major cause of human cancer

nitrosamine (nitrosoguanidine)
extreme skin sensitivity to UV

xeroderma pigmentosum
AP endonucleases cleave

ends with what enzyme

cleave the DNA adjacent to apurinic and apyrimidic site ( at the 5' end of DNA)

ligase sesals the nick
for repairing the deamination of cytosine to uracil

break the glycosidic bond between the U and deoxyribose

Uracil-DNA glcosylase
sequences of enzymes used after Uracil -DNA glycosylase

AP endonuclease, DNA polymerase, DNA ligase
what happens if cytosine go through deamination to hypoxanthine

hypoxanthine glycosylase removes hypoxanthine from DNA
hypoxanthine base pairs with what

C

Author

neotinky

2081

Card Set

46-47

Description

mutagens and types of mutations

Updated

2009-12-02T04:59:46Z