The mutagenic properties of BrdUTP in a random mutagenesis process.
To explore the mutagenic properties of the nucleotide analogue bromodeoxyuridine triphosphate (BrdUTP), the wild type alpha-amylase (xamy) gene from Xanthomonas campestris pv. campestris 8004 was used as a mutational target. It was mutated using PCR techniques to partially replace deoxythymidine triphosphate (dTTP) with BrdUTP. A total of 18 mutants were selected for DNA sequencing from the mutagenesis libraries by their ability to hydrolyze the starch. The results showed that 70% of the total mutations were single base-pair substitutions; BrdUTP also induced deletion and insertion mutation types. Among single base-pair substitutions, the predominant mutation type is transition (84%), but three kinds of transversions (16%) were also detected. It thus mainly induces A:T --> G:C and T:A --> C:G transitions. This result indicated that when bromouracil is present as a deoxyribonucleoside triphosphate substrate it mainly paired with dAMP, and when it is present as a template base it could pair with free dGTP. Three mutational hot spots induced by BrdUTP were revealed in this work.
Ma
Xiangdong
X
College of Life Science, Hubei University, Wuhan, 430062, China.
Ke
Tao
T
Mao
Peihong
P
Jin
Xiang
X
Ma
Lixin
L
He
Guangyuan
G
D020137:Base Pair Mismatch; D004269:DNA, Bacterial / Q000235:genetics; D003856:Deoxyuracil Nucleotides / Q000378:metabolism*; D016296:Mutagenesis; D009154:Mutation; D016133:Polymerase Chain Reaction; D013942:Thymine Nucleotides / Q000737:chemistry; D016959:Xanthomonas campestris / Q000201:enzymology; D000516:alpha-Amylases / Q000235:genetics / Q000378:metabolism
D004269:DNA, Bacterial; D003856:Deoxyuracil Nucleotides; D013942:Thymine Nucleotides; C032549:bromodeoxyuridine triphosphate; D000516:alpha-Amylases; C024157:thymidine 5'-triphosphate