Seongmin Lee
University of Texas at Austin
Publications 40
#1Yi KouH-Index: 5
#2Myong-Chul KoagH-Index: 2
Last.Seongmin LeeH-Index: 13
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Chronic inflammation is closely associated with cancer development. One possible mechanism for inflammation-induced carcinogenesis is DNA damage caused by reactive halogen species, such as hypochlorous acid, which is released by myeloperoxidase to kill pathogens. Hypochlorous acid can attack genomic DNA to produce 8-chloro-2′-deoxyguanosine (ClG) as a major lesion. It has been postulated that ClG promotes mutagenic replication using its syn conformer; yet, the structural basis for ClG-induced mu...
#1Myong-Chul Koag (University of Texas at Austin)H-Index: 2
#2Hunmin Jung (University of Texas at Austin)
Last.Seongmin Lee (University of Texas at Austin)H-Index: 13
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Reactive oxygen species attack DNA to produce 7,8-dihyro-8-oxoguanine (oxoG) and 7,8-dihydro-8-oxoadenine (oxoA) as major lesions. The structural basis for the mutagenicity of oxoG, which induces G to T mutations, is well understood. However, the structural basis for the mutagenic potential of oxoA, which induces A to C mutations, remains poorly understood. To gain insight into oxoA-induced mutagenesis, we conducted kinetic studies of human DNA polymerases β and η replicating across oxoA and str...
#1Aaron Leland Rozelle (University of Texas at Austin)
#2Rayala Naveen Kumar (University of Texas at Austin)H-Index: 5
Last.Seongmin Lee (University of Texas at Austin)H-Index: 13
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Oxaliplatin, together with cisplatin, is among the most important drugs used in cancer chemotherapy. Oxaliplatin, which contains a bulky diaminocyclohexane (DACH) moiety, kills cancer cells mainly by producing (DACH)Pt–GpG intrastrand cross-links that impede transcription. The Pt–GpG tolerance by translesion DNA synthesis (TLS) polymerases contributes to the resistance of tumors to platinum-based chemotherapy. In particular, human DNA polymerase η (Polη) readily bypasses Pt–GpG adducts. While ma...
#1Yi Kou (University of Texas at Austin)H-Index: 5
#2Myong-Chul Koag (University of Texas at Austin)H-Index: 2
Last.Seongmin Lee (University of Texas at Austin)H-Index: 13
view all 3 authors...
A wide variety of endogenous and exogenous alkylating agents attack DNA to preferentially generate N7-alkylguanine (N7-alkylG) adducts. Studies of the effect of N7-alkylG lesions on biological processes have been difficult in part because of complications arising from the chemical lability of the positively charged N7-alkylG, which can readily produce secondary lesions. To assess the effect of bulky N7-alkylG on DNA replication, we prepared chemically stable N7-benzylguanine (N7bnG)-containing D...
#1Myong-Chul Koag (University of Texas at Austin)H-Index: 2
#2Seongmin Lee (University of Texas at Austin)H-Index: 13
DNA polymerases accommodate various base pair conformations in the event of incorrect insertions. In particular, Watson-Crick-like dG:dTTP base pair has been observed at the insertion site of human DNA polymerase β (pol β). A potential factor contributing to the diverse conformations of base pair mismatches is minor groove interactions. To gain insight into the effect of minor groove interactions on base pair conformations, we generated an Asn279Ala polβ mutant that cannot make minor groove cont...
#1Young Cheun (University of Texas at Austin)H-Index: 4
#2Myong Chul Koag (University of Texas at Austin)H-Index: 7
Last.Seongmin Lee (University of Texas at Austin)H-Index: 13
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Cisplatin resistance is caused, in part, by the efficient removal of the helix-distorting cisplatin 1,2-intrastrand crosslinks by nucleotide excision repair (NER) machinery. To make a platinum-DNA adduct that causes less helical distortion than the cisplatin 1,2-intrastrand adduct, we designed and synthesized a monofunctional platinum-carbazole conjugate (carbazoleplatin). The 2.5A crystal structure of carbazoleplatin-DNA adduct revealed both the monoplatination of the N7 of a guanine (G) base a...
#1Rayala Naveen Kumar (University of Texas at Austin)H-Index: 5
#2Seongmin Lee (University of Texas at Austin)H-Index: 13
Abstract Cephalostatins, ritterazines and their hybrid bis-steroidal pyrazine analogs such as 25- epi -rittereostatin G N 1 N show unusually high potency against a wide range of cancer cell lines. Herein, we report the synthesis and bioactivity of 23-deoxy-25- epi ritterostatin G N 1 N , which lacks the 23-hydroxyl group of 25- epi rittereostatin G N 1 N . The less oxygenated bis-steroidal pyrazine was ∼50- to 1000-fold less potent than 25- epi ritterostatin G N 1 N , highlighting the importance...