title: Crystallization and preliminary crystallographic analysis of calcium-binding protein-2 from Entamoeba histolytica and its complexes with strontium and the IQ1 motif of myosin V.
abstract: Calcium plays a pivotal role in the pathogenesis of amoebiasis, a major disease caused by Entamoeba histolytica. Two domains with four canonical EF-hand-containing calcium-binding proteins (CaBPs) have been identified from E. histolytica. Even though they have very high sequence similarity, these bind to different target proteins in a Ca2+-dependent manner, leading to different functional pathways. Calcium-binding protein-2 (EhCaBP2) crystals were grown using MPD as a precipitant. The crystals belong to space group P2(1), with unit-cell parameters a = 111.74, b = 68.83, c = 113.25 A, beta = 116.7 degrees. EhCaBP2 also crystallized in complex with strontium (replacing calcium) at similar conditions. The crystals belong to space group P2(1), with unit-cell parameters a = 69.18, b = 112.03, c = 93.42 A, beta = 92.8 degrees. Preliminary data for EhCaBP2 crystals in complex with an IQ motif are also reported. This complex was crystallized with MPD and ethanol as precipitating agents. These crystals belong to space group P2(1), with unit-cell parameters a = 60.5, b = 69.86, c = 86.5 A, beta = 97.9 degrees.
authors.affiliation: School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India. sgourinath@mail.jnu.ac.in
authors.forename: S
authors.initials: S
authors.lastname: Gourinath
authors.forename: Narendra
authors.initials: N
authors.lastname: Padhan
authors.forename: Neelima
authors.initials: N
authors.lastname: Alam
authors.forename: Alok
authors.initials: A
authors.lastname: Bhattacharya
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D002135:Calcium-Binding Proteins / Q000737:chemistry*; D011232:Chemical Precipitation; D003460:Crystallization / Q000379:methods; D004748:Entamoeba histolytica / Q000737:chemistry*; D024701:Myosin Type V / Q000737:chemistry*; D015800:Protozoan Proteins / Q000737:chemistry; D013324:Strontium / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D002135:Calcium-Binding Proteins; D015800:Protozoan Proteins; D024701:Myosin Type V; C085578:Ca-binding protein 2; D013324:Strontium