Re: [spctools-discuss] Re: Searching specific taxonomy using Tandem in TPP GUI

2010-10-22 Thread James Broadbent
subsetdb worked perfectly! Thanks again! On Fri, Oct 22, 2010 at 12:36 PM, James Broadbent james.broadb...@gmail.com wrote: Thank you both for the advice. That helps a lot! The subsetdb.exe. is just what I'm after as I'm trying to extract human only sequences from swissprot/uniprot. I've

Re: [spctools-discuss] Re: Searching specific taxonomy using Tandem in TPP GUI

2010-10-22 Thread James Broadbent
Thank you both for the advice. That helps a lot! The subsetdb.exe. is just what I'm after as I'm trying to extract human only sequences from swissprot/uniprot. I've been trying to use sed in bash to extract the identifiers to then create a new database, but have had no luck so far. I'll run

[spctools-discuss] ASAP Ratio with Mascot Search

2010-10-22 Thread Mike
I am having a problem with using ASAP ratio to quantify mTRAQ labeled samples. Starting with .RAW files from Thermo, I convert to mzXML, and then convert to .mgf for database searching. I search the samples using MASCOT with variable modifications on the n-Terminus and lysine residues for both

Re: [spctools-discuss] ASAP Ratio with Mascot Search

2010-10-22 Thread Jimmy Eng
 Similarly, if only the difference between light and heavy residues are entered for XPRESS, how does this program know the mass of the light and heavy tagged residues? Regarding this question, XPRESS doesn't need to know the mass of the tagged residues as that information isn't necessary.

[spctools-discuss] Re: ASAP Ratio with Mascot Search

2010-10-22 Thread Mike
Thanks for your prompt reply Jimmy. It is clear to me how XPRESS calculates the mass difference between light and heavy labeled peptides. As you describe, this is simply a matter of knowing the number of labeled residues in the peptide and the associated mass differences. It is unclear how the

Re: [spctools-discuss] Re: ASAP Ratio with Mascot Search

2010-10-22 Thread Jimmy Eng
Determining light or heavy peptide is simple and shouldn't be a black box: No variable mods on the specified residues equals light peptide. Variable mods on all of the specified residues equals heavy peptide. If there's a mixture (in your case an unmodified + a modified lysine in the same

[spctools-discuss] Re: ASAP Ratio with Mascot Search

2010-10-22 Thread Mike
In the MASCOT search, I specify a variable modification for the n- terminus and lysine residue for both light and heavy tags. This allows for the identification of unlabeled peptides. In this framework, no variable mods is unlabeled, whereas variable mod with an addition of 140 Da is light and

Re: [spctools-discuss] Re: ASAP Ratio with Mascot Search

2010-10-22 Thread Ben Collins
Hi Mike, Not sure if this is helpful or not but I've been able to make ASAPratio work with binary chemical labeling (reductive dimethylation in my case) by doing two separate searches with the light label specified as a static mod in one and the heavy label specified as a static mod in the other.

Re: [spctools-discuss] Re: ASAP Ratio with Mascot Search

2010-10-22 Thread Jimmy Eng
In the scenario you describe, XPRESS would think that all of the identified peptides were heavy and quantify the corresponding light partner by always subtracting a mass from the identified peptide mass. So check your results to confirm whether or not this is the case; I'd have to think that half