[ccp4bb] Two postdoctoral positions at the Karolinska Institutet for studying mitochondrial gene expression and genome segregation

2019-07-31 Thread Martin Hällberg
Dear all, We have two funded postdoctoral positions available to investigate mitochondrial gene expression and genome-segregation mechanisms primarily using cryo-EM but also biochemistry and macromolecular crystallography (MX). We are located in the newly-built Biomedicum on the northern campu

Re: [ccp4bb] question on charge charge interactions

2014-03-27 Thread Martin Hällberg
Hi Tom, For acidic side-chains, these kind of interactions are described by Maria Flocco and Sherry Mowbray in: "Strange bedfellows: interactions between acidic side-chains in proteins." J. Mol. Biol. (1995) 254, 96-105. Best regards, Martin On Mar 28, 2014, at 12:11 AM, Tom Peat wrote: >

[ccp4bb] Two Postdoctoral Positions – Structural Biochemistry of Mitochondrial RNA Biogenesis

2012-12-19 Thread Martin Hällberg
Two Postdoctoral Positions – Structural Biochemistry of Mitochondrial RNA Biogenesis Successful candidates will participate in all steps involved in structure determination of DNA/RNA/protein complexes relevant to mitochondrial RNA biogenesis in the laboratory of Martin Hallberg at the Karolinsk

Re: [ccp4bb] Crack-resistant tubes for centrifugation

2012-01-31 Thread Martin Hällberg
Raji, we use the 50 ml Cornings up to 25K RCF in our F13S-14x50cy rotor without leakage so it could be a batch specific problem with your Corning tubes. Try to talk to Piramoon or one their resellers (Thermo?) in your country if they have some batches of 50 ml tubes in stock that they can guaran

Re: [ccp4bb] secondary structure output

2012-01-24 Thread Martin Hällberg
You can try STRIDE2PyMOL: http://pldserver1.biochem.queensu.ca/~rlc/work/pymol/stride_ss.py /Martin On Jan 24, 2012, at 9:57 PM, Ed Pozharski wrote: > I am looking for a program/server that would determine secondary > structure from a pdb file and then output a new pdb file with > HELIX/SHEET r

Re: [ccp4bb] Manually setting 96 wells plates with lower volume samples!

2011-11-18 Thread Martin Hällberg
Hi, With the electronic Biohit 8 channel pipette you can set up 3x96 drops in 5 minutes. Lowest volume is 0.2 ul. We have used this system for a couple of years with RNase free filter tips for RNA-protein complexes. With the recent arrival of a shared Mosquito we have used the Biohit less but it

Re: [ccp4bb] Experimental phasing with 50% twin

2011-05-15 Thread Martin Hällberg
Dear Phil, Is the twin fraction varying? Can you correlate the variation of twin fraction with variations in crystal morphology or handling? With constant perfect twinning you could try MIR using the phase determination method of Yates & Rees (Acta Cryst. (1987). A43, 30-36). I can't access the

Re: [ccp4bb] Tev Cleavage issue !!

2011-04-08 Thread Martin Hällberg
Dear Anita, Sometimes the protein of interest has a relatively strong inherent binding affinity to the IMAC column. Have you tried to bind the cleavage reaction to an IMAC column and then elute using a shallow imidazole gradient? In fact, Porath developed IMAC chromatography as a tool for prote

Re: [ccp4bb] Synthetic RNA for Crystallization

2011-03-13 Thread Martin Hällberg
Hi, I'll second Israels's comment. Since the yield per coupling in synthesis is lower for RNA than for DNA it gets really expensive over 30-35 nucleotides. However, you can stitch together several 30 nt oligos using either T4 RNA ligase or T4 DNA ligase (with a DNA splint). Regarding suppliers