Re: [ccp4bb] VERY old mtz file..

2018-11-13 Thread Zhijie Li
It's also said here, at the end of file : https://www.cs.auckland.ac.nz/~patrice/210LN/DR4.pdf "add 1 to the left, with the binary point" 0.1. From: CCP4 bulletin board on behalf of Zhijie Li Sent: Tuesday, November 13, 2018 7:43 PM To: CCP4BB@JISCM

Re: [ccp4bb] VERY old mtz file..

2018-11-13 Thread Zhijie Li
Hi all, I think I know why it is a division of 4 instead of 2 is involved in conversion from VAX to IEEE now. Short answer: a 2 is in the exponent bits (bias of 128 instead of 127, visible), another 2 is hidden in the scientific notation. I found this explanation+example on VAX F-float: http

[ccp4bb] Postdoctoral position in ion channel mechanism with cryo-EM available in the laboratory of Crina Nimigean at Weill Cornell Medical College in New York City

2018-11-13 Thread Crina Nimigean
Postdoctoral position in ion channel mechanism with cryo-EM available in the laboratory of Crina Nimigean at Weill Cornell Medical College in New York City There is an availability in the laboratory of Crina Nimigean for an enthusiastic postdoc who is interested in the molecular workings of ion

Re: [ccp4bb] VERY old mtz file..

2018-11-13 Thread Ian Tickle
Hi Zhijie It's definitely a factor 4. The code is in subroutine QTIEEE in the Fortran source I mentioned previously at this line: See line: A(I)=((A(I)+SIGN(2,A(I)))/4.AND..NOT.MNAN).OR.MDN2 If you prefer it in C code it's in function vaxF2ieeeF in: ccp4-7.0-src/checkout/libccp4/ccp4/vm

Re: [ccp4bb] VERY old mtz file..

2018-11-13 Thread Phil
MTZ was always 32 bit floats for the main data, with ASCII headers at the end Sent from my iPhone > On 13 Nov 2018, at 21:29, Ethan A Merritt wrote: > >> On Tuesday, November 13, 2018 1:06:01 PM PST Zhijie Li wrote: >> Hi Ethan, >> Thanks for the information. My guess is that in MTZ only F-floa

Re: [ccp4bb] VERY old mtz file..

2018-11-13 Thread Ethan A Merritt
On Tuesday, November 13, 2018 1:06:01 PM PST Zhijie Li wrote: > Hi Ethan, > Thanks for the information. My guess is that in MTZ only F-float is expected, > because it is the only 32bit form? I do not remember exactly what was used for mtz files at that time. It might have been REAL*4 or it might

Re: [ccp4bb] VERY old mtz file..

2018-11-13 Thread Zhijie Li
Hi Ethan, Thanks for the information. My guess is that in MTZ only F-float is expected, because it is the only 32bit form? Zhijie > On Nov 13, 2018, at 3:44 PM, Ethan A Merritt wrote: > >> On Tuesday, November 13, 2018 11:51:55 AM PST Zhijie Li wrote: >> If somebody is going to send these file

Re: [ccp4bb] VERY old mtz file..

2018-11-13 Thread Keller, Jacob
>> ah, nostalgia Ah, "mantissa!" Haven't heard "mantissa" in decades... Is there such a thing as a "praying mantissa?" Seems like there could be a good geek joke about it. JPK > However all procedures I have seen use a division of 4, which is quite > puzzling to me. A real data file co

Re: [ccp4bb] VERY old mtz file..

2018-11-13 Thread Ethan A Merritt
On Tuesday, November 13, 2018 11:51:55 AM PST Zhijie Li wrote: > If somebody is going to send these files by email, please send one to me too. > Thanks in advance. I actually prefer to get a MTZ file because the miller > indices would serve as good clues for understanding the encodings. Even the

Re: [ccp4bb] VERY old mtz file..

2018-11-13 Thread Zhijie Li
If somebody is going to send these files by email, please send one to me too. Thanks in advance. I actually prefer to get a MTZ file because the miller indices would serve as good clues for understanding the encodings. Even the first 1024 bytes of an MTZ would do (data array starts at byte 80 i

Re: [ccp4bb] Asn/Gln - pi-stacking prevalence

2018-11-13 Thread Daniel Anderson
While working on PDB entries 1F0N and 1F0P, I aligned the side-chain dipoles of 4 asparagines with the side-chain dipoles of tryptophans (ring nitrogen is slightly negative, the rest of the 5-membered ring is slightly positive). Aligning dipoles simultaneously optimized hydrogen bonding for the

Re: [ccp4bb] VERY old mtz file..

2018-11-13 Thread Johan Hattne
Related by not exactly on topic: would anybody on the list be able to share old map files (not MTZ:s) with Convex, Cray, Fujitsu, or VAX reals/strings? I’d be interested to see what those files actually look(ed) like. // Best wishes; Johan > On Nov 9, 2018, at 18:38, Zhijie Li wrote: > > Hi

Re: [ccp4bb] OFF TOPIC

2018-11-13 Thread PULSARSTRIAN
Hi Anamika, As far as I understood, the biotin in the elution buffer is helping your protein to get stripped off from the Avidin column. So, maybe you dialyze your purified protein (or run FPLC) and get rid of biotin completely, before you load the protein on to strptavidin coa

[ccp4bb] Call Postdoctoral Fellowship Program at the Helmholtz Zentrum München, Munich, Germany

2018-11-13 Thread Ana Messias
Call Postdoctoral Fellowship Program at the Helmholtz Zentrum München, Munich, Germany Deadline November 30 , 2018 The PFP trains highly talented early-career scientists for leadership positions in health and environment research. It includes an individual career development plan, coaching an

Re: [ccp4bb] OFF TOPIC

2018-11-13 Thread Jonathan Elegheert
Hi Anamika, - Have you double-checked that the sequence of your cDNA is correct and includes the biotin acceptor peptide tag (BAP tag aka AviTag; GLNDIFEAQKIEWHE in single-letter amino acid code)? - Are you using a dedicated bacterial strain that over-expresses BirA enzyme? This may not be str

Re: [ccp4bb] OFF TOPIC

2018-11-13 Thread Thomas Edwards
You don’t say so, but one assumes that you have a BAP tag on the protein, and co-express a biotin ligase such as BirA? Ed T.A.Edwards Ph.D. Associate Professor of Biochemistry Deputy Head of School _ Astbury Centre for Structural Molecular Biology School of M

Re: [ccp4bb] OFF TOPIC

2018-11-13 Thread Wim Burmeister
Hello, you probably purified a contaminant. Do a blot with an anti-biotin antibody or get electro-spray mass spectrometry done in order to confirm the identity of your protein. Wim On 13/11/2018 11:13, Anamika Singh wrote: Hi All,

[ccp4bb] OFF TOPIC

2018-11-13 Thread Anamika Singh
Hi All, I am purifying the biotinylated protein (cloned into the pET28a vector) using Avidin beads. Since I need the protein for SPR but when I used the purified protein to interact with Streptavidin coated onto the SPR chip. There was no signal. Can anybody tell me why is it so or how can I make

[ccp4bb] CCP4 Study Weekend Early Bird ending

2018-11-13 Thread Charles Ballard - UKRI STFC
Dear All a heads up that the early bird registration, and closing date for student bursaries, is Sunday 18th November 2018 i.e. this Sunday! For more info see http://www.cvent.com/d/sgq8q6/1K?cpc=N7N8SK89V8N Regards Karen McIntyre Scientific Computing Department - CCP4 ###