[ccp4bb] weird--No protein expression using pET30a

2012-03-17 Thread Jerry McCully
Dear ALL; Recently, one of my colleagues cloned a gene (200aa) into pET30a vectors with either a N-ter or C-ter His6 tag. The correct reading frame was confirmed by sequencing. However, it is weird that there was no protein expression either in the soluble fraction or as

Re: [ccp4bb] Help! weird thing

2012-03-17 Thread Eleanor Dodson
pseudo translation is very common and usually does not pose a serious problem. you have to be careful about assigning the space group, since a translation od x,y,z=1/2 will generate absences for l = 2n+1 which may suggest a screw axis along c . But since your space group is P21 that isn't a

Re: [ccp4bb] weird--No protein expression using pET30a

2012-03-17 Thread Santosh
Hi Jerry: There are many instances where we miss going through process of sequencing the entire reading frame, as many sequencing cores provides sequences only upto 600-700 bases, I would recommend sequencing a complete reading frame using mid frame primers and then conclude whether the reading

[ccp4bb] cloning HD

2012-03-17 Thread Hena Dutta
Hello, Sorry for the question if non-ccp4. I am using a HP workstation Xeon Z400. This has both windows and linux Mint. I am using crystallographic programs with stereo setup in coot, o, pymol, vmd…. I bought a new exactly same desktop with all same hardware configurations except the old one has

Re: [ccp4bb] cloning HD

2012-03-17 Thread Ed Pozharski
On Sat, 2012-03-17 at 08:44 -0400, Hena Dutta wrote: I tried with clonezill and it did not work. There are many problems with what you are trying to do. 1. Windows license is tied to the hardware, thus it's not likely to work out of the box if you clone the whole drive. 2. Even though it's

Re: [ccp4bb] Help! weird thing

2012-03-17 Thread Ed Pozharski
One comment I'd like to add here is that in the presence of pseudo-translational ncs that is nearly colinear with crystal axes you will have a significantly higher R-value. This may be a serious problem with some reviewers when your R~30% on a 2A dataset. It is completely justified then to have