Dear Rana, It appears that you have helical biopolymers formed by the proteins. Given the size of 630 kDa as the unit cell or the asymmetric unit forming the biopolymer you have a fair chance of gaining insight to the proteins. Using cryo EM you have to collect a sizeable amount of data , followed by computing Fourier Transform of the filaments. Using the transform you have to index and determine the Axial Rise and turn angle of the filaments. You can then choose any program available freely online to calculate the density map of the filaments, thus the proteins. You may want to look in
http://3dem.ucsd.edu/software.shtm under Helices. I will recommend you to use BSOFT and FreAlign www.bsoft.ws http://grigoriefflab.janelia.org/frealign Combination of these two yield pretty good results.Keep in mind that such a work is a complete project in itself. Best wishes Anindito Sen. Ph.D Scientist & Application Specialist in Biological Sciences JEOL LTD. 13F, Ohtemachi Nomura Bldg 2-1-1 Ohtemachi Chiyoda-Ku. Tokyo, Japan Tel: +81-3-6262-3563 Fax: +81-3-6262-3577 www.jeol.com On Aug 30, 2014, at 1:29 AM, rana ibd <rna19792...@yahoo.com> wrote: > > Dear Anindito > Thank you for your reply and I apologize for writing the wrong name, I work > on the HBx proteins which contain molecular weights of (56, 57, 59)kDa > including a tag, but they are all polymers and in size exclusion > chromatography for the three proteins give a size of 630kDa > Best Regards > Rana > > From: Andy Sen <andysen.to...@gmail.com> > To: CCP4BB@JISCMAIL.AC.UK > Sent: Friday, August 29, 2014 5:06 PM > Subject: Re: [ccp4bb] cryo-EM > > Dear Rana, > > Brad's post compelled me to reply to you. The Cryo EM field is well into its > pro stage. > > If you can be specific about the MolWt, size and if it makes any complex, > then much precise and helpful answers to your question can be provided. > > Best > > Anindito Sen Ph.D > JeoL > > > On 29/08/2014, at 11:31 pm, Marcus Fislage <mf2...@columbia.edu> wrote: > > > > Hi Rana, > > > > in contrast to Brads answer, and in case I understand you well, Cryo EM is > > not in ts infancy stage (as long as you do not talk about Cryo EM on > > crystals. > > For cryo EM you need only several ul of a nM solution. > > I can always suggest you the 3dem bb. There are of course still > > limitataions on the size of protein target and resolution, but those are > > slowly falling. > > > > Some reading material > > http://www.ncbi.nlm.nih.gov/pubmed/23181775 > > http://www.ncbi.nlm.nih.gov/pubmed/25071206 > > > > > > Cheers > > Marcus > > > > Quoting Brad Bennett <bradbennet...@gmail.com>: > > > >> Yes, but the technique is still in its infancy stage. > >> > >> DOI: 10.1016/j.sbi.2014.03.004 > >> > >> Cheers- > >> Brad > >> > >> > >> On Fri, Aug 29, 2014 at 6:34 AM, rana ibd < > >> 00000285de88044a-dmarc-requ...@jiscmail.ac.uk> wrote: > >> > >>> Dear CCP4 > >>> I wanted to ask has anyone tested 3D protein structure by cryo-electron > >>> microscopy? what is the suitable concentration required for this procedure > >>> Best Regards > >>> Rana > > > > > > > > -- > > Marcus Fislage, PhD > > > > Howard Hughes Medical Institute (HHMI) > > Columbia University > > Department of Biochemistry and Biophysics > > Lab of Joachim Frank > > New York, NY > > > > Phone: 212.305.9524 > > Fax: 212.305.9500 >
