Re: [ccp4bb] pH optimisation for crystallisation

2012-02-08 Thread Xiaodi Yu
Xiaodi Date: Wed, 8 Feb 2012 11:56:30 +0530 From: somon_...@yahoo.co.in Subject: [ccp4bb] pH optimisation for crystallisation To: CCP4BB@JISCMAIL.AC.UK Dear all, I have a 17 KDa protein that gives crystals in a condition that has 0.1M bis-tris pH 6.5. The crystals are thin needle

Re: [ccp4bb] pH optimisation for crystallisation

2012-02-08 Thread Tom Peat
, sometimes. Yu Xiaodi Date: Wed, 8 Feb 2012 11:56:30 +0530 From: somon_...@yahoo.co.in Subject: [ccp4bb] pH optimisation for crystallisation To: CCP4BB@JISCMAIL.AC.UK Dear all, I have a 17 KDa protein that gives crystals in a condition that has 0.1M bis

[ccp4bb] pH optimisation for crystallisation

2012-02-07 Thread sreetama das
Dear all,    I have a 17 KDa protein that gives crystals in a condition that has 0.1M bis-tris pH 6.5. The crystals are thin needle clusters and do not diffract. I have tried additives, but they haven't improved the crystals. I intend to vary the pH of the condition.    My

Re: [ccp4bb] pH optimisation for crystallisation

2012-02-07 Thread VAN RAAIJ , MARK JOHAN
Dear Sreetama, First of all, there are no hard-and-fast rules for successful crystallisation, try changing as many different variables as possible and go with what works. Having said that, yes, next I would go for a grid optimisation varying the pH in 0.2 or 0.5 units over as wide a range