HEADER LUMINESCENT PROTEIN 13-MAR-00 1EL4 TITLE STRUCTURE OF THE CALCIUM-REGULATED PHOTOPROTEIN OBELIN DETERMINED BY TITLE 2 SULFUR SAS COMPND MOL_ID: 1; COMPND 2 MOLECULE: OBELIN; COMPND 3 CHAIN: A; COMPND 4 SYNONYM: OBL; COMPND 5 ENGINEERED: YES SOURCE MOL_ID: 1; SOURCE 2 ORGANISM_SCIENTIFIC: OBELIA LONGISSIMA; SOURCE 3 ORGANISM_TAXID: 32570; SOURCE 4 EXPRESSION_SYSTEM: ESCHERICHIA COLI; SOURCE 5 EXPRESSION_SYSTEM_TAXID: 562; SOURCE 6 EXPRESSION_SYSTEM_VECTOR_TYPE: PLASMID; SOURCE 7 EXPRESSION_SYSTEM_PLASMID: PT7-7 KEYWDS BIOLUMINESCENCE, CALCIUM, PHOTOPROTEIN, OBELIN, SULFUR ANOMALOUS KEYWDS 2 SCATTERING, LUMINESCENT PROTEIN EXPDTA X-RAY DIFFRACTION AUTHOR Z.J.LIU,E.S.VYSOTSKI,J.ROSE,J.LEE,B.C.WANG REVDAT 4 07-FEB-24 1EL4 1 REMARK REVDAT 3 24-FEB-09 1EL4 1 VERSN REVDAT 2 01-APR-03 1EL4 1 JRNL REVDAT 1 13-MAR-01 1EL4 0 JRNL AUTH Z.J.LIU,E.S.VYSOTSKI,C.J.CHEN,J.P.ROSE,J.LEE,B.C.WANG JRNL TITL STRUCTURE OF THE CA2+-REGULATED PHOTOPROTEIN OBELIN AT 1.7 A JRNL TITL 2 RESOLUTION DETERMINED DIRECTLY FROM ITS SULFUR SUBSTRUCTURE. JRNL REF PROTEIN SCI. V. 9 2085 2000 JRNL REFN ISSN 0961-8368 JRNL PMID 11152120 REMARK 1 REMARK 1 REFERENCE 1 REMARK 1 AUTH E.S.VYSOTSKI,Z.J.LIU,J.ROSE,B.C.WANG,J.LEE REMARK 1 TITL PREPARATION AND PRELIMINARY STUDY OF CRYSTALS OF THE REMARK 1 TITL 2 RECOMBINANT CALCIUM-REGULATED PHOTOPROTEIN OBELIN FROM THE REMARK 1 TITL 3 BIOLUMINESCENT HYDROID OBELIA LONGISSIMA REMARK 1 REF ACTA CRYSTALLOGR.,SECT.D V. 55 1965 1999 REMARK 1 REFN ISSN 0907-4449 REMARK 1 DOI 10.1107/S0907444999011828 REMARK 2 REMARK 2 RESOLUTION. 1.73 ANGSTROMS. REMARK 3 REMARK 3 REFINEMENT. REMARK 3 PROGRAM : CNS REMARK 3 AUTHORS : BRUNGER,ADAMS,CLORE,DELANO,GROS,GROSSE- REMARK 3 : KUNSTLEVE,JIANG,KUSZEWSKI,NILGES,PANNU, REMARK 3 : READ,RICE,SIMONSON,WARREN REMARK 3 REMARK 3 REFINEMENT TARGET : ENGH & HUBER REMARK 3 REMARK 3 DATA USED IN REFINEMENT. REMARK 3 RESOLUTION RANGE HIGH (ANGSTROMS) : 1.73 REMARK 3 RESOLUTION RANGE LOW (ANGSTROMS) : 19.84 REMARK 3 DATA CUTOFF (SIGMA(F)) : 0.000 REMARK 3 DATA CUTOFF HIGH (ABS(F)) : 260910.230 REMARK 3 DATA CUTOFF LOW (ABS(F)) : 0.0000 REMARK 3 COMPLETENESS (WORKING+TEST) (%) : 97.5 REMARK 3 NUMBER OF REFLECTIONS : 33058 REMARK 3 REMARK 3 FIT TO DATA USED IN REFINEMENT. REMARK 3 CROSS-VALIDATION METHOD : THROUGHOUT REMARK 3 FREE R VALUE TEST SET SELECTION : RANDOM REMARK 3 R VALUE (WORKING SET) : 0.188 REMARK 3 FREE R VALUE : 0.205 REMARK 3 FREE R VALUE TEST SET SIZE (%) : 8.100 REMARK 3 FREE R VALUE TEST SET COUNT : 2665 REMARK 3 ESTIMATED ERROR OF FREE R VALUE : 0.004 REMARK 3 REMARK 3 FIT IN THE HIGHEST RESOLUTION BIN. REMARK 3 TOTAL NUMBER OF BINS USED : 6 REMARK 3 BIN RESOLUTION RANGE HIGH (A) : 1.73 REMARK 3 BIN RESOLUTION RANGE LOW (A) : 1.84 REMARK 3 BIN COMPLETENESS (WORKING+TEST) (%) : 88.60 REMARK 3 REFLECTIONS IN BIN (WORKING SET) : 4611 REMARK 3 BIN R VALUE (WORKING SET) : 0.2610 REMARK 3 BIN FREE R VALUE : 0.3020 REMARK 3 BIN FREE R VALUE TEST SET SIZE (%) : 7.50 REMARK 3 BIN FREE R VALUE TEST SET COUNT : 372 REMARK 3 ESTIMATED ERROR OF BIN FREE R VALUE : 0.016 REMARK 3 REMARK 3 NUMBER OF NON-HYDROGEN ATOMS USED IN REFINEMENT. REMARK 3 PROTEIN ATOMS : 1556 REMARK 3 NUCLEIC ACID ATOMS : 0 REMARK 3 HETEROGEN ATOMS : 34 REMARK 3 SOLVENT ATOMS : 266 REMARK 3 REMARK 3 B VALUES. REMARK 3 FROM WILSON PLOT (A**2) : 17.50 REMARK 3 MEAN B VALUE (OVERALL, A**2) : 18.60 REMARK 3 OVERALL ANISOTROPIC B VALUE. REMARK 3 B11 (A**2) : 0.87000 REMARK 3 B22 (A**2) : 0.87000 REMARK 3 B33 (A**2) : -1.75000 REMARK 3 B12 (A**2) : 0.98000 REMARK 3 B13 (A**2) : 0.00000 REMARK 3 B23 (A**2) : 0.00000 REMARK 3 REMARK 3 ESTIMATED COORDINATE ERROR. REMARK 3 ESD FROM LUZZATI PLOT (A) : 0.18 REMARK 3 ESD FROM SIGMAA (A) : 0.15 REMARK 3 LOW RESOLUTION CUTOFF (A) : 5.00 REMARK 3 REMARK 3 CROSS-VALIDATED ESTIMATED COORDINATE ERROR. REMARK 3 ESD FROM C-V LUZZATI PLOT (A) : 0.21 REMARK 3 ESD FROM C-V SIGMAA (A) : 0.18 REMARK 3 REMARK 3 RMS DEVIATIONS FROM IDEAL VALUES. REMARK 3 BOND LENGTHS (A) : 0.005 REMARK 3 BOND ANGLES (DEGREES) : 1.100 REMARK 3 DIHEDRAL ANGLES (DEGREES) : 19.60 REMARK 3 IMPROPER ANGLES (DEGREES) : 0.710 REMARK 3 REMARK 3 ISOTROPIC THERMAL MODEL : NULL REMARK 3 REMARK 3 ISOTROPIC THERMAL FACTOR RESTRAINTS. RMS SIGMA REMARK 3 MAIN-CHAIN BOND (A**2) : 1.300 ; 1.500 REMARK 3 MAIN-CHAIN ANGLE (A**2) : 1.840 ; 2.000 REMARK 3 SIDE-CHAIN BOND (A**2) : 2.480 ; 2.000 REMARK 3 SIDE-CHAIN ANGLE (A**2) : 3.590 ; 2.500 REMARK 3 REMARK 3 BULK SOLVENT MODELING. REMARK 3 METHOD USED : FLAT MODEL REMARK 3 KSOL : 0.37 REMARK 3 BSOL : 47.16 REMARK 3 REMARK 3 NCS MODEL : NULL REMARK 3 REMARK 3 NCS RESTRAINTS. RMS SIGMA/WEIGHT REMARK 3 GROUP 1 POSITIONAL (A) : NULL ; NULL REMARK 3 GROUP 1 B-FACTOR (A**2) : NULL ; NULL REMARK 3 REMARK 3 PARAMETER FILE 1 : PROTEIN_REP.PARAM REMARK 3 PARAMETER FILE 2 : ION.PARAM REMARK 3 PARAMETER FILE 3 : CROM5.PAR REMARK 3 PARAMETER FILE 4 : WATER.PARAM REMARK 3 PARAMETER FILE 5 : NULL REMARK 3 TOPOLOGY FILE 1 : PROTEIN.TOP REMARK 3 TOPOLOGY FILE 2 : ION.TOP REMARK 3 TOPOLOGY FILE 3 : CROM5.TOP REMARK 3 TOPOLOGY FILE 4 : WATER.TOP REMARK 3 TOPOLOGY FILE 5 : NULL REMARK 3 REMARK 3 OTHER REFINEMENT REMARKS: REMARK 3 THE STRUCTURE WAS DETERMINED USING SINGLE WAVELENGTH REMARK 3 ANOMALOUS SCATTERING DATA RECORDED FOR THE NATIVE PROTEIN. REMARK 3 DATA WERE RECORDED ON TWO OBELIN CRYSTALS TO 2.5 ANGSTROMS REMARK 3 RESOLUTION AT BEAMLINE ID-17 (IMCA-CAT), ADVANCED PHOTON REMARK 3 SOURCE (APS), ARGONNE NATIONAL LABORATORY USING A REMARK 3 MARRESEARCH 165 MM CCD DETECTOR AND 1.74 ANGSTROM X-RAYS. REMARK 3 A DATA COLLECTION STRATEGY (HKL2000) WAS DETERMINED FROM REMARK 3 THE INITIAL IMAGE TO GIVE THE STARTING AND ENDING POINTS OF REMARK 3 THE DATA COLLECTION TO INSURE A MINIMUM DATA COMPLETENESS REMARK 3 OF 98 PERCENT. DATA WERE COLLECTED USING THE "FREIDEL REMARK 3 FLIP" METHOD. DATA PROCESSING WAS CARRIED OUT USING REMARK 3 HKL2000. THE PROCESSED DATA FORMING THE TWO DATA SETS WERE REMARK 3 MERGED TO INCREASE REDUNDANCY (WU, ET AL., (2000) J. PROT. REMARK 3 PEP. LETTS. 7, 25-32) AND SOLVE WAS USED TO DETERMINE THE REMARK 3 SIX OF THE EIGHT SULFUR ATOM POSITIONS. PHASES WAS USED REMARK 3 TO REFINE THE SULFUR POSITIONS AND TO LOCATE THE REMAINING REMARK 3 SULFUR SITES BY BIJVOET DIFFERENCE FOURIER ANALYSIS. THREE REMARK 3 ADDITIONAL SITES WERE IDENTIFIED SUGGESTING THAT ONE OF THE REMARK 3 SULFUR SITES WAS MOST PROBABLY AN ANOMALOUS SOLVENT SUCH AS REMARK 3 CHLORIDE. ALL ANOMALOUS SITES WERE TREATED AS SULFUR FOR REMARK 3 THE PHASE CALCULATIONS. REMARK 3 THE NINE SULFUR SITES WERE USED TO ESTIMATE THE INITIAL REMARK 3 PROTEIN PHASES AT 3 ANGSTROM RESOLUTION USING SOLVENT REMARK 3 FLATTENING (ISAS, WANG, (1985) METHODS ENZYMOL. 115, 90 REMARK 3 112). A PRELIMINARY CHAIN TRACE WAS DONE USING THE 3.0 REMARK 3 ANGSTROM MAP. SEQUENCE ASSIGNMENT WAS BASED ON 8 SULFUR REMARK 3 ATOM POSITIONS. THE MODEL, 99 PERCENT COMPLETE WAS BUILT REMARK 3 USING THE 3.0 ANGSTROM SAS MAP. RESIDUE 1 WAS NOT REMARK 3 OBSERVED IN THE ELECTRON DENSITY AMPS AND IS PRESUMED TO BE REMARK 3 DISORDERED. REMARK 3 THE RESOLUTION OF THE STRUCTURE WAS THEN EXTENDED TO 1.73 REMARK 3 ANGSTROMS RESOLUTION DURING THE FINAL STAGES OF REFINEMENT REMARK 3 USING A MERGED DATA SET COLLECTED FROM A SINGLE CRYSTAL REMARK 3 RECORDED AT APS (BEAMLINE ID19, WAVELENGTH 0.94 ANGSTROMS) REMARK 3 AND AT ALS (BEAMLINE 5.0.2, WAVELENGTH 1.0 ANGSTROMS). REMARK 4 REMARK 4 1EL4 COMPLIES WITH FORMAT V. 3.30, 13-JUL-11 REMARK 100 REMARK 100 THIS ENTRY HAS BEEN PROCESSED BY RCSB ON 20-MAR-00. REMARK 100 THE DEPOSITION ID IS D_1000010696. REMARK 200 REMARK 200 EXPERIMENTAL DETAILS REMARK 200 EXPERIMENT TYPE : X-RAY DIFFRACTION REMARK 200 DATE OF DATA COLLECTION : 18-SEP-99; 10-JUN-99; 05-APR-99 REMARK 200 TEMPERATURE (KELVIN) : 100; 100; 100 REMARK 200 PH : 6.0 REMARK 200 NUMBER OF CRYSTALS USED : 3 REMARK 200 REMARK 200 SYNCHROTRON (Y/N) : Y; Y; Y REMARK 200 RADIATION SOURCE : APS; APS; ALS REMARK 200 BEAMLINE : 17-ID; 19-ID; 5.0.2 REMARK 200 X-RAY GENERATOR MODEL : NULL; NULL; NULL REMARK 200 MONOCHROMATIC OR LAUE (M/L) : M; NULL; NULL REMARK 200 WAVELENGTH OR RANGE (A) : 1.74; 0.94; 1.0 REMARK 200 MONOCHROMATOR : NULL; NULL; NULL REMARK 200 OPTICS : NULL; NULL; NULL REMARK 200 REMARK 200 DETECTOR TYPE : CCD; CCD; CCD REMARK 200 DETECTOR MANUFACTURER : MARRESEARCH; APS-1; ADSC QUANTUM REMARK 200 4 REMARK 200 INTENSITY-INTEGRATION SOFTWARE : HKL-2000 REMARK 200 DATA SCALING SOFTWARE : HKL-2000 REMARK 200 REMARK 200 NUMBER OF UNIQUE REFLECTIONS : 33694 REMARK 200 RESOLUTION RANGE HIGH (A) : 1.730 REMARK 200 RESOLUTION RANGE LOW (A) : 20.000 REMARK 200 REJECTION CRITERIA (SIGMA(I)) : 2.000 REMARK 200 REMARK 200 OVERALL. REMARK 200 COMPLETENESS FOR RANGE (%) : 99.5 REMARK 200 DATA REDUNDANCY : 5.800 REMARK 200 R MERGE (I) : 0.03800 REMARK 200 R SYM (I) : NULL REMARK 200 <I/SIGMA(I)> FOR THE DATA SET : 37.6000 REMARK 200 REMARK 200 IN THE HIGHEST RESOLUTION SHELL. REMARK 200 HIGHEST RESOLUTION SHELL, RANGE HIGH (A) : 1.73 REMARK 200 HIGHEST RESOLUTION SHELL, RANGE LOW (A) : 1.79 REMARK 200 COMPLETENESS FOR SHELL (%) : 97.1 REMARK 200 DATA REDUNDANCY IN SHELL : 5.00 REMARK 200 R MERGE FOR SHELL (I) : 0.21600 REMARK 200 R SYM FOR SHELL (I) : NULL REMARK 200 <I/SIGMA(I)> FOR SHELL : NULL REMARK 200 REMARK 200 DIFFRACTION PROTOCOL: SINGLE WAVELENGTH; NULL; NULL REMARK 200 METHOD USED TO DETERMINE THE STRUCTURE: SULFUR SAS REMARK 200 SOFTWARE USED: SOLVE FOLLOWED BY ISAS, ISAS REMARK 200 STARTING MODEL: NULL REMARK 200 REMARK 200 REMARK: STRUCTURE DETERMINED USING THE SULFUR SAS SIGNAL RECORDED REMARK 200 AT ID17, APS USING 1.74 ANGSTROM X-RAYS (SEE REMARK 3 REFINEMENT REMARK 200 DETAILS) REMARK 280 REMARK 280 CRYSTAL REMARK 280 SOLVENT CONTENT, VS (%): 62.00 REMARK 280 MATTHEWS COEFFICIENT, VM (ANGSTROMS**3/DA): 3.79 REMARK 280 REMARK 280 CRYSTALLIZATION CONDITIONS: HANGING DROP VAPOR DIFFUSION USING 5 REMARK 280 MICROLITER DROPS CONTAINING EQUAL VOLUMES OF PROTEIN CONCENTRATE REMARK 280 (10 MG/ML) AND RESERVOIR SOLUTION: CONTAINING 1.4 M SODIUM REMARK 280 CITRATE, PH 6.0., VAPOR DIFFUSION, HANGING DROP, TEMPERATURE 277K REMARK 290 REMARK 290 CRYSTALLOGRAPHIC SYMMETRY REMARK 290 SYMMETRY OPERATORS FOR SPACE GROUP: P 62 REMARK 290 REMARK 290 SYMOP SYMMETRY REMARK 290 NNNMMM OPERATOR REMARK 290 1555 X,Y,Z REMARK 290 2555 -Y,X-Y,Z+2/3 REMARK 290 3555 -X+Y,-X,Z+1/3 REMARK 290 4555 -X,-Y,Z REMARK 290 5555 Y,-X+Y,Z+2/3 REMARK 290 6555 X-Y,X,Z+1/3 REMARK 290 REMARK 290 WHERE NNN -> OPERATOR NUMBER REMARK 290 MMM -> TRANSLATION VECTOR REMARK 290 REMARK 290 CRYSTALLOGRAPHIC SYMMETRY TRANSFORMATIONS REMARK 290 THE FOLLOWING TRANSFORMATIONS OPERATE ON THE ATOM/HETATM REMARK 290 RECORDS IN THIS ENTRY TO PRODUCE CRYSTALLOGRAPHICALLY REMARK 290 RELATED MOLECULES. REMARK 290 SMTRY1 1 1.000000 0.000000 0.000000 0.00000 REMARK 290 SMTRY2 1 0.000000 1.000000 0.000000 0.00000 REMARK 290 SMTRY3 1 0.000000 0.000000 1.000000 0.00000 REMARK 290 SMTRY1 2 -0.500000 -0.866025 0.000000 0.00000 REMARK 290 SMTRY2 2 0.866025 -0.500000 0.000000 0.00000 REMARK 290 SMTRY3 2 0.000000 0.000000 1.000000 57.39200 REMARK 290 SMTRY1 3 -0.500000 0.866025 0.000000 0.00000 REMARK 290 SMTRY2 3 -0.866025 -0.500000 0.000000 0.00000 REMARK 290 SMTRY3 3 0.000000 0.000000 1.000000 28.69600 REMARK 290 SMTRY1 4 -1.000000 0.000000 0.000000 0.00000 REMARK 290 SMTRY2 4 0.000000 -1.000000 0.000000 0.00000 REMARK 290 SMTRY3 4 0.000000 0.000000 1.000000 0.00000 REMARK 290 SMTRY1 5 0.500000 0.866025 0.000000 0.00000 REMARK 290 SMTRY2 5 -0.866025 0.500000 0.000000 0.00000 REMARK 290 SMTRY3 5 0.000000 0.000000 1.000000 57.39200 REMARK 290 SMTRY1 6 0.500000 -0.866025 0.000000 0.00000 REMARK 290 SMTRY2 6 0.866025 0.500000 0.000000 0.00000 REMARK 290 SMTRY3 6 0.000000 0.000000 1.000000 28.69600 REMARK 290 REMARK 290 REMARK: NULL REMARK 300 REMARK 300 BIOMOLECULE: 1 REMARK 300 SEE REMARK 350 FOR THE AUTHOR PROVIDED AND/OR PROGRAM REMARK 300 GENERATED ASSEMBLY INFORMATION FOR THE STRUCTURE IN REMARK 300 THIS ENTRY. THE REMARK MAY ALSO PROVIDE INFORMATION ON REMARK 300 BURIED SURFACE AREA. REMARK 300 REMARK: THE BIOLOGICAL ASSEMBLY IS A MONOMER. REMARK 350 REMARK 350 COORDINATES FOR A COMPLETE MULTIMER REPRESENTING THE KNOWN REMARK 350 BIOLOGICALLY SIGNIFICANT OLIGOMERIZATION STATE OF THE REMARK 350 MOLECULE CAN BE GENERATED BY APPLYING BIOMT TRANSFORMATIONS REMARK 350 GIVEN BELOW. BOTH NON-CRYSTALLOGRAPHIC AND REMARK 350 CRYSTALLOGRAPHIC OPERATIONS ARE GIVEN. REMARK 350 REMARK 350 BIOMOLECULE: 1 REMARK 350 AUTHOR DETERMINED BIOLOGICAL UNIT: MONOMERIC REMARK 350 APPLY THE FOLLOWING TO CHAINS: A REMARK 350 BIOMT1 1 1.000000 0.000000 0.000000 0.00000 REMARK 350 BIOMT2 1 0.000000 1.000000 0.000000 0.00000 REMARK 350 BIOMT3 1 0.000000 0.000000 1.000000 0.00000 REMARK 465 REMARK 465 MISSING RESIDUES REMARK 465 THE FOLLOWING RESIDUES WERE NOT LOCATED IN THE REMARK 465 EXPERIMENT. (M=MODEL NUMBER; RES=RESIDUE NAME; C=CHAIN REMARK 465 IDENTIFIER; SSSEQ=SEQUENCE NUMBER; I=INSERTION CODE.) REMARK 465 REMARK 465 M RES C SSSEQI REMARK 465 MET A 1 REMARK 500 REMARK 500 GEOMETRY AND STEREOCHEMISTRY REMARK 500 SUBTOPIC: TORSION ANGLES REMARK 500 REMARK 500 TORSION ANGLES OUTSIDE THE EXPECTED RAMACHANDRAN REGIONS: REMARK 500 (M=MODEL NUMBER; RES=RESIDUE NAME; C=CHAIN IDENTIFIER; REMARK 500 SSEQ=SEQUENCE NUMBER; I=INSERTION CODE). REMARK 500 REMARK 500 STANDARD TABLE: REMARK 500 FORMAT:(10X,I3,1X,A3,1X,A1,I4,A1,4X,F7.2,3X,F7.2) REMARK 500 REMARK 500 EXPECTED VALUES: GJ KLEYWEGT AND TA JONES (1996). PHI/PSI- REMARK 500 CHOLOGY: RAMACHANDRAN REVISITED. STRUCTURE 4, 1395 - 1400 REMARK 500 REMARK 500 M RES CSSEQI PSI PHI REMARK 500 ASP A 12 57.99 -152.09 REMARK 500 ASP A 49 -73.77 -104.86 REMARK 500 SER A 145 72.31 -153.65 REMARK 500 REMARK 500 REMARK: NULL REMARK 800 REMARK 800 SITE REMARK 800 SITE_IDENTIFIER: AC1 REMARK 800 EVIDENCE_CODE: SOFTWARE REMARK 800 SITE_DESCRIPTION: BINDING SITE FOR RESIDUE CL A 196 REMARK 800 REMARK 800 SITE_IDENTIFIER: AC2 REMARK 800 EVIDENCE_CODE: SOFTWARE REMARK 800 SITE_DESCRIPTION: BINDING SITE FOR RESIDUE CTZ A 197 DBREF 1EL4 A 1 195 UNP Q27709 OBL_OBELO 1 195 SEQRES 1 A 195 MET SER SER LYS TYR ALA VAL LYS LEU LYS THR ASP PHE SEQRES 2 A 195 ASP ASN PRO ARG TRP ILE LYS ARG HIS LYS HIS MET PHE SEQRES 3 A 195 ASP PHE LEU ASP ILE ASN GLY ASN GLY LYS ILE THR LEU SEQRES 4 A 195 ASP GLU ILE VAL SER LYS ALA SER ASP ASP ILE CYS ALA SEQRES 5 A 195 LYS LEU GLU ALA THR PRO GLU GLN THR LYS ARG HIS GLN SEQRES 6 A 195 VAL CYS VAL GLU ALA PHE PHE ARG GLY CYS GLY MET GLU SEQRES 7 A 195 TYR GLY LYS GLU ILE ALA PHE PRO GLN PHE LEU ASP GLY SEQRES 8 A 195 TRP LYS GLN LEU ALA THR SER GLU LEU LYS LYS TRP ALA SEQRES 9 A 195 ARG ASN GLU PRO THR LEU ILE ARG GLU TRP GLY ASP ALA SEQRES 10 A 195 VAL PHE ASP ILE PHE ASP LYS ASP GLY SER GLY THR ILE SEQRES 11 A 195 THR LEU ASP GLU TRP LYS ALA TYR GLY LYS ILE SER GLY SEQRES 12 A 195 ILE SER PRO SER GLN GLU ASP CYS GLU ALA THR PHE ARG SEQRES 13 A 195 HIS CYS ASP LEU ASP ASN SER GLY ASP LEU ASP VAL ASP SEQRES 14 A 195 GLU MET THR ARG GLN HIS LEU GLY PHE TRP TYR THR LEU SEQRES 15 A 195 ASP PRO GLU ALA ASP GLY LEU TYR GLY ASN GLY VAL PRO HET CL A 196 1 HET CTZ A 197 33 HETNAM CL CHLORIDE ION HETNAM CTZ C2-HYDROXY-COELENTERAZINE HETSYN CTZ 8-BENZYL-2-HYDROXY-2-(4-HYDROXY-BENZYL)-6-(4-HYDROXY- HETSYN 2 CTZ PHENYL)-2H-IMIDAZO[1,2-A]PYRAZIN-3-ONE FORMUL 2 CL CL 1- FORMUL 3 CTZ C26 H21 N3 O4 FORMUL 4 HOH *266(H2 O) HELIX 1 1 ASN A 15 ASP A 30 1 16 HELIX 2 2 THR A 38 ASP A 48 1 11 HELIX 3 3 ASP A 49 LEU A 54 1 6 HELIX 4 4 THR A 57 GLY A 74 1 18 HELIX 5 5 PHE A 85 ARG A 105 1 21 HELIX 6 6 THR A 109 PHE A 122 1 14 HELIX 7 7 THR A 131 GLY A 143 1 13 HELIX 8 8 SER A 147 CYS A 158 1 12 HELIX 9 9 VAL A 168 TYR A 180 1 13 HELIX 10 10 ASP A 183 ASP A 187 5 5 SHEET 1 A 2 LYS A 36 ILE A 37 0 SHEET 2 A 2 ILE A 83 ALA A 84 -1 N ILE A 83 O ILE A 37 SHEET 1 B 2 THR A 129 ILE A 130 0 SHEET 2 B 2 LEU A 166 ASP A 167 -1 O LEU A 166 N ILE A 130 SITE 1 AC1 4 ARG A 112 THR A 172 HOH A 301 HOH A 303 SITE 1 AC2 16 HIS A 22 MET A 25 ILE A 42 ILE A 50 SITE 2 AC2 16 PHE A 88 TRP A 92 TRP A 114 GLY A 115 SITE 3 AC2 16 PHE A 119 TRP A 135 TYR A 138 MET A 171 SITE 4 AC2 16 HIS A 175 TRP A 179 TYR A 190 HOH A 239 CRYST1 81.562 81.562 86.088 90.00 90.00 120.00 P 62 6 ORIGX1 1.000000 0.000000 0.000000 0.00000 ORIGX2 0.000000 1.000000 0.000000 0.00000 ORIGX3 0.000000 0.000000 1.000000 0.00000 SCALE1 0.012261 0.007079 0.000000 0.00000 SCALE2 0.000000 0.014157 0.000000 0.00000 SCALE3 0.000000 0.000000 0.011616 0.00000