X-ray driven reduction of Cpd I of Catalase-3 from N. crassa reveals differential sensitivity of active sites and formation of ferrous state

Journal Article · 30 March 2019 · Archives of Biochemistry and Biophysics

DOI: https://doi.org/10.1016/j.abb.2019.03.020 · OSTI ID:1532492

Zárate-Romero, Andrés ^[1]; Stojanoff, Vivian ^[2]; Cohen, Aina E. ^[3]; Hansberg, Wilhelm ^[4]; Rudiño-Piñera, Enrique ^[5]

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1. Universidad Nacional Autónoma de México, Ensenada, B. C. (Mexico)
2. Brookhaven National Lab. (BNL), Upton, NY (United States)
3. Stanford Univ., Menlo Park, CA (United States). Stanford Synchrotron Radiation LIghtsource.
4. Universidad Nacional Autónoma de México, Ciudad de México (Mexico)
5. Universidad Nacional Autónoma de México, Cuernavaca, Morelos (Mexico)

Catalases are biotechnologically relevant enzymes due to their applications in food technology, bioremediation, and biomedicine. The dismutation of hydrogen peroxide occurs in two steps; in the first one, the enzyme forms an oxidized compound I (Cpd I) and in the second one, the enzyme is reduced to the ferric state. In this research work, we analyzed the reduction of Cpd I by X-ray radiation damage during diffraction experiments in crystals of CAT-3, a Large-Size Subunit Catalase (LSC) from Neurospora crassa. A Multi-Crystal Data collection Strategy was applied in order to obtain the Cpd I structure at a resolution of 2.2 Å; this intermediate was highly sensitive to X-ray and was easily reduced at very low deposited radiation dose, causing breakage of the Fe=O bond. The comparison of the structures reflected reduced intermediates and also evidenced the differential sensitivity per monomer. The resting ferric state was reduced to the ferrous state, an intermediate without a previous report in LSC. The chemically obtained Cpd I and the X-ray reduced intermediates were identified by UV-visible microspectrometry coupled to data collection. The differential sensitivity and the formation of a ferrous state are discussed, emphasizing the importance of the correct interpretation in the oxidation state of the iron heme.

• Research Organization: SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Office of Science (SC), Biological and Environmental Research (BER); National Institutes of Health (NIH); National Institute of General Medical Sciences; USDOE
• Grant/Contract Number: PAPIIT IN204611; GM-0080; AC02-98CH10886; AC02-76SF00515; SC0012704
• OSTI ID: 1532492
• Alternate ID(s): OSTI ID: 1546050; OSTI ID: 1547569
• Report Number(s): BNL-211925-2019-JAAM
• Journal Information: Archives of Biochemistry and Biophysics, Vol. 666, Issue C; ISSN 0003-9861
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English