Article info Vol. 5  No. 3   pp.  107 ~ 109
Title Phase determination of a homogentisate dioxygenase from Comamonas sp. strain P19
Authors Suk-Youl Park1, Byoung Yul Soh2, Jong-Chan Chae3 and Jeong-Sun Kim4*
Institutions 1Pohang Accelerator Laboratory, Pohang University of Science and Technology, 80 Jigokro-127-Beongil, Nam-gu, Pohang, Gyeongbuk 37673, Korea, 2Department of Biochemistry, College of Medicine, Seonam University, Namwon 55724, Republic of Korea, 3Division of Biotechnology, Chonbuk National University, Iksan 54596, Republic of Korea, 4Department of Chemistry, College of Natural Sciences, Chonnam National University, Yongbong-ro 77, Buk-gu, Gwangju 61186, Korea. *Correspondence: jsunkim@chonnam.ac.kr
Abstract In Comamonas sp. strain P19, homogentisate 1,2-dioxygenase (HGO) catalyzes the conversion of homogentisate to 4-maleylacetoacetate by aromatic ring scission, in the breakdown of tyrosine and phenylalanine. To determine the molecular background of the enzymatic mechanism of HGO in this zinc-resistant organism, hmgA encoding HGO of Comamonas sp. strain P19 was cloned, and the expressed protein was purified. The protein was crystallized in solutions I [25% (w/v) polyethylene glycol 3350 and 0.1 M trisodium citrate at pH 5.6] and II [1.4 M ammonium tartrate and 0.1 M bis- Tris at pH 5.5]. X-ray diffraction data were collected to 1.8 Å resolution using synchrotron radiation. The crystal belongs to the orthorhombic space group P212121, with unit cell dimensions of a = 73.2 Å, b = 100.0 Å, and c = 134.9 Å. A traceable electron density map was calculated using anomalous diffraction data obtained from a crystal soaked in zinc ions.