well yes, looks like a glycosylation to me too. However, at 2.75Å resolution I think it will be impossible to know which one from the density alone. Perhaps mass spectroscopy can give a clue? Or get clues from what is known about your protein and your expression system.
Mark J van Raaij Dpto de Estructura de Macromoleculas Centro Nacional de Biotecnologia - CSIC calle Darwin 3 E-28049 Madrid, Spain tel. (+34) 91 585 4616 http://wwwuser.cnb.csic.es/~mjvanraaij > On 26 Jan 2017, at 15:45, KH. HEROJIT SINGH, PH D SCHOLAR, PCL > <[email protected]> wrote: > > Dear All, > > > A continuous map from gamma O of serine at expose region was observed. > Resolution of dataset is 2.75 A. The serine position is predicted for > phosphorylation in-sillico. With fitting with mannose, density is not fully > satisfied while with GalNac, some negative density is found. > > > Condition was 15% PEG 3350, Tris 50mM pH 7, 100mM Na2SO4and buffer was tris > 50mM, NaCl 50mM, ph 8.5 , 1mM PMSF. Images from different angle are attached > (File size is 300Kb). Arrow in fig pointed the same serine residue. > > > Kindly suggest. > > -- > Regards, > KHUNDRAKPAM HEROJIT > Ph D SCHOLAR > PROTEIN CRYSTALLOGRAPHY LAB. > NATIONAL INSTITUTE OF IMMUNOLOGY > NEW DELHI-110067, INDIA<ccp4.jpg>
