1
|
Powell SM, Prather KY, Nguyen N, Thomas LM, Richter-Addo GB. Interactions of metronidazole and chloramphenicol with myoglobin: Crystal structure of a Mb-acetamide product. J PORPHYR PHTHALOCYA 2023; 27:1142-1147. [PMID: 37868702 PMCID: PMC10588810 DOI: 10.1142/s1088424623500700] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2023]
Abstract
Nitroorganics present a general concern for a safe environment due to their health hazards. However, some nitroorganics such as metronidazole (Mtz) and chloramphenicol (CAM) also possess medicinal value. Mtz and CAM can undergo reductive bioactivation presumably via their nitroso derivatives. We show, using UV-vis spectroscopy, that sperm whale myoglobin (swMb) and its distal pocket mutants retaining H-bonding capacity react with Mtz in the presence of dithionite to generate products with spectra suggestive of the Fe-bound nitroso (Fe-RNO; λmax ~420 nm) forms. We have crystallized and solved the X-ray crystal structure of an H64Q swMb-acetamide compound to 1.76 Å resolution; formation of this compound results from the serendipitous crystallographic trapping, by the heme center, of acetamide from the reductive decomposition of Mtz. Only one of the swMb proteins, namely H64Q swMb with a relatively flexible Gln64 residue, reacted with CAM presumably due to the bulky nature of CAM that generally may restrict its access to the heme site.
Collapse
Affiliation(s)
- Samantha M. Powell
- Price Family Foundation Institute of Structural Biology, Stephenson Life Sciences Research Center, and Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK, U.S.A. 73019
- Biological Sciences Division, Pacific Northwest National Laboratory, 902 Batelle Blvd, Richland, WA, U.S.A. 99352
| | - Kiana Y. Prather
- Price Family Foundation Institute of Structural Biology, Stephenson Life Sciences Research Center, and Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK, U.S.A. 73019
- University of Oklahoma College of Medicine, 800 Stanton L. Young Blvd, Oklahoma City, OK 73117
| | - Nancy Nguyen
- Price Family Foundation Institute of Structural Biology, Stephenson Life Sciences Research Center, and Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK, U.S.A. 73019
- University of Oklahoma College of Medicine, 800 Stanton L. Young Blvd, Oklahoma City, OK 73117
| | - Leonard M. Thomas
- Price Family Foundation Institute of Structural Biology, Stephenson Life Sciences Research Center, and Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK, U.S.A. 73019
| | - George B. Richter-Addo
- Price Family Foundation Institute of Structural Biology, Stephenson Life Sciences Research Center, and Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK, U.S.A. 73019
| |
Collapse
|
2
|
Mutlu A, Yeşil T, Kıymaz D, Zafer C. Simultaneous Optimization of Charge Transport Properties in a Triple-Cation Perovskite Layer and Triple-Cation Perovskite/Spiro-OMeTAD Interface by Dual Passivation. ACS OMEGA 2022; 7:17907-17920. [PMID: 35664622 PMCID: PMC9161386 DOI: 10.1021/acsomega.2c01195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 05/06/2022] [Indexed: 06/15/2023]
Abstract
Molecular engineering of additives is a highly effective method to increase the efficiency of perovskite solar cells by reducing trap states and charge carrier barriers in bulk and on the thin film surface. In particular, the elimination of undercoordinated lead species that act as the nonradiative charge recombination center or contain defects that may limit interfacial charge transfer is critical for producing a highly efficient triple-cation perovskite solar cell. Here, 2-iodoacetamide (2I-Ac), 2-bromoacetamide (2Br-Ac), and 2-chloroacetamide (2Cl-Ac) molecules, which can be coordinated with lead, have been used by adding them into a chlorobenzene antisolvent to eliminate the defects encountered in the triple-cation perovskite thin film. The passivation process has been carried out with the coordination between the oxygen anion (-) and the lead (+2) cation on the enolate molecule, which is in the resonance structure of the molecules. The Spiro-OMeTAD/triple-cation perovskite interface has been improved by surface passivation by releasing HX (X = I, Br) as a byproduct because of the separation of alpha hydrogen on the molecule. As a result, a solar cell with a negligible hysteresis operating at 19.5% efficiency has been produced by using the 2Br-Ac molecule, compared to the 17.6% efficiency of the reference cell.
Collapse
Affiliation(s)
- Adem Mutlu
- Solar Energy Institute, Ege University, 35100 Izmir, Turkey
| | - Tamer Yeşil
- Solar Energy Institute, Ege University, 35100 Izmir, Turkey
| | - Deniz Kıymaz
- Solar Energy Institute, Ege University, 35100 Izmir, Turkey
| | - Ceylan Zafer
- Solar Energy Institute, Ege University, 35100 Izmir, Turkey
| |
Collapse
|