Analysis of a nuclease activity of catalytic domain of Thermus thermophilus MutS2 by high-accuracy mass spectrometry.
Electrospray ionization with Fourier-transform ion cyclotron resonance mass spectrometry (ESI-FT ICR MS) is a powerful tool for analyzing the precise structural features of biopolymers, including oligonucleotides. Here, we described the detailed characterization of a newly discovered nuclease activity of the C-terminal domain of Thermus thermophilus MutS2 (ttMutS2). Using this method, the length, nucleotide content and nature of the 5'- and 3'-termini of the product oligonucleotides were accurately identified. It is revealed that the C-terminal domain of ttMutS2 incised the phosphate backbone of oligodeoxynucleotides non-sequence-specifically at the 3' side of the phosphates. The simultaneous identification of the innumerable fragments was achieved by the extremely high-accuracy of ESI-FT ICR MS.
RIKEN SPring-8 Center, Harima Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.
Kenji
K
Fukui
Yoshio
Y
Takahata
Noriko
N
Nakagawa
Seiki
S
Kuramitsu
Ryoji
R
Masui
D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D020134:Catalytic Domain; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004706:Endodeoxyribonucleases / Q000737:chemistry / Q000378:metabolism*; D005583:Fourier Analysis; D051718:MutS Homolog 2 Protein / Q000737:chemistry / Q000378:metabolism*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D016963:Thermus thermophilus / Q000201:enzymology*
D001426:Bacterial Proteins; D004247:DNA; D004706:Endodeoxyribonucleases; D051718:MutS Homolog 2 Protein