6N21:
reference: Evidence for distinct rate-limiting steps in the cleavage of alkenes by carotenoid cleavage dioxygenases., Khadka N, Farquhar ER, Hill HE, Shi W, von Lintig J, Kiser PD, J Biol Chem. 2019 May 28. pii: RA119.007535. doi: 10.1074/jbc.RA119.007535. PMID: 31138651

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