2H1V:
reference: Amino Acid Residues His183 and Glu264 in Bacillus subtilis Ferrochelatase Direct and Facilitate the Insertion of Metal Ion into Protoporphyrin IX(,)., Hansson MD, Karlberg T, Rahardja MA, Al-Karadaghi S, Hansson M, Biochemistry. 2007 Jan 9;46(1):87-94. PMID: 17198378

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