An amyloid-like fibril-forming supramolecular cross-β-structure of a model peptide: a crystallographic insight.
Maity, Sibaprasad; Kumar, Pankaj; Haldar, Debasish; Organic & biomolecular chemistry 9 (2011) 3787–3791; doi:10.1039/c0ob01033b

data_7151809
_publ_section_title
;
 An amyloid-like fibril-forming supramolecular cross-\b-structure of a
 model peptide: a crystallographic insight.
;
_journal_issue                   10
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              3787
_journal_page_last               3791
_journal_paper_doi               10.1039/c0ob01033b
_journal_volume                  9
_journal_year                    2011
_chemical_absolute_configuration syn
_chemical_formula_moiety         'C20 H30 N2 O5'
_chemical_formula_sum            'C20 H30 N2 O5'
_chemical_formula_weight         378.46
_chemical_melting_point          356
_chemical_name_common
methyl-2-(2-(tert-butoxycarbonylamino)-3-methylbutanamido)-3-phenylpropanoate
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   5.1057(5)
_cell_length_b                   10.2051(12)
_cell_length_c                   40.956(4)
_cell_measurement_reflns_used    2545
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      21.00
_cell_measurement_theta_min      2.23
_cell_volume                     2134.0(4)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0634
_diffrn_reflns_av_sigmaI/netI    0.0534
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       42
_diffrn_reflns_limit_l_min       -43
_diffrn_reflns_number            14620
_diffrn_reflns_theta_full        22.25
_diffrn_reflns_theta_max         22.25
_diffrn_reflns_theta_min         0.99
_exptl_absorpt_coefficient_mu    0.084
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.178
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       rod
_exptl_crystal_F_000             816
_exptl_crystal_size_max          0.41
_exptl_crystal_size_mid          0.23
_exptl_crystal_size_min          0.13
_refine_diff_density_max         0.165
_refine_diff_density_min         -0.148
_refine_diff_density_rms         0.035
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -1(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.938
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     250
_refine_ls_number_reflns         2710
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.938
_refine_ls_R_factor_all          0.0694
_refine_ls_R_factor_gt           0.0453
_refine_ls_shift/su_max          0.026
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0811P)^2^+0.3763P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1091
_refine_ls_wR_factor_ref         0.1315
_reflns_number_gt                2070
_reflns_number_total             2710
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c0ob01033b.txt
_cod_data_source_block           sm
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1555 2011-01-17 13:19:09Z saulius 

The following automatic conversions were performed:

'_chemical_melting_point' value '356K' was changed to '356' - the
value should be numeric and without a unit designator.

Automatic conversion script
Id: cif_fix_values 1569 2011-02-09 13:29:24Z adriana 
;
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               7151809