Crystal and molecular structure of muga wild silk fibres based on [Ala-Gly]n sequence using LALS technique
نویسندگان
چکیده
X-ray diffraction pattern of muga wild silk fibres has been recorded using imaging plate system (Dip-100S). In order to identify various Bragg reflections and to compute X-ray intensities of these reflections, fibre processing software (CCP13) has been used. A molecular model is first constructed with standard bond lengths and angles using helical symmetry and layer-line spacing observed in the X-ray pattern. The model is then refined against observed X-ray data using linked atom least squares method. The crystal and molecular structure of muga wild silk fibres are compared with reported domestic and wild silk fibre. We could get good R–factor with refinement of a model having beta-pleated sheet structures formed by hydrogen bonds having antipolar – antiparallel arrangement.
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