Dataset Information

Characterization of the Intermediate in and Identification of the Repair Mechanism of (6-4) Photolesions by Photolyases.

ABSTRACT: Quantum mechanics/molecular mechanics calculations are employed to assign previously recorded experimental spectroscopic signatures of the intermediates occurring during the photo-induced repair of (6-4) photolesions by photolyases to specific molecular structures. Based on this close comparison of experiment and theory it is demonstrated that the acting repair mechanism involves proton transfer from the protonated His365 to the N3' nitrogen of the lesion, which proceeds simultaneously with intramolecular OH transfer along an oxetane-like transition state.

SUBMITTER: Faraji S

PROVIDER: S-EPMC4921128 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Characterization of the Intermediate in and Identification of the Repair Mechanism of (6-4) Photolesions by Photolyases.

Faraji Shirin S Zhong Dongping D Dreuw Andreas A

Angewandte Chemie (International ed. in English) 20160321 17

Quantum mechanics/molecular mechanics calculations are employed to assign previously recorded experimental spectroscopic signatures of the intermediates occurring during the photo-induced repair of (6-4) photolesions by photolyases to specific molecular structures. Based on this close comparison of experiment and theory it is demonstrated that the acting repair mechanism involves proton transfer from the protonated His365 to the N3' nitrogen of the lesion, which proceeds simultaneously with intr ...[more]

PMID: 26996356

Similar Datasets

Project description:Fungal conidia serve as active ingredients of fungal insecticides but are sensitive to solar UV irradiation, which impairs double-stranded DNA (dsDNA) by inducing the production of cytotoxic cyclobutane pyrimidine dimers (CPDs) and (6-4)-pyrimidine-pyrimidine photoproducts (6-4PPs). This study aims to elucidate how CPD photolyase (Phr1) and 6-4PP photolyase (Phr2) repair DNA damage and photoreactivate UVB-inactivated cells in Beauveria bassiana, a main source of fungal insecticides. Both Phr1 and Phr2 are proven to exclusively localize in the fungal nuclei. Despite little influence on growth, conidiation, and virulence, singular deletions of phr1 and phr2 resulted in respective reductions of 38% and 19% in conidial tolerance to UVB irradiation, a sunlight component most harmful to formulated conidia. CPDs and 6-4PPs accumulated significantly more in the cells of ?phr1 and ?phr2 mutants than in those of a wild-type strain under lethal UVB irradiation and were largely or completely repaired by Phr1 in the ?phr2 mutant and Phr2 in the ?phr1 mutant after optimal 5-h exposure to visible light. Consequently, UVB-inactivated conidia of the ?phr1 and ?phr2 mutants were much less efficiently photoreactivated than were the wild-type counterparts. In contrast, overexpression of either phr1 or phr2 in the wild-type strain resulted in marked increases in both conidial UVB resistance and photoreactivation efficiency. These findings indicate essential roles of Phr1 and Phr2 in photoprotection of B. bassiana from UVB damage and unveil exploitable values of both photolyase genes for improved UVB resistance and application strategy of fungal insecticides.IMPORTANCE Protecting fungal cells from damage from solar UVB irradiation is critical for development and application of fungal insecticides but is mechanistically not understood in Beauveria bassiana, a classic insect pathogen. We unveil that two intranuclear photolyases, Phr1 and Phr2, play essential roles in repairing UVB-induced dsDNA lesions through respective decomposition of cytotoxic cyclobutane pyrimidine dimers and (6-4)-pyrimidine-pyrimidine photoproducts, hence reactivating UVB-inactivated cells effectively under visible light. Our findings shed light on the high potential of both photolyase genes for use in improving UVB resistance and application strategy of fungal insecticides.

Dataset Information

Characterization of the Intermediate in and Identification of the Repair Mechanism of (6-4) Photolesions by Photolyases.

Publications

Characterization of the Intermediate in and Identification of the Repair Mechanism of (6-4) Photolesions by Photolyases.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets