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FASTF/TFASTFv3(1)	     General Commands Manual	       FASTF/TFASTFv3(1)

NAME
     fastf3, fastf3_t - compare a mixed peptide sequence against a protein data-
     base using a modified fasta algorithm.

     tfastf3,  tfastf3_t  - compare a mixed pepide sequence against a translated
     DNA database.

DESCRIPTION
     fastf3 and tfastf3 are designed to compare a sequence of mixed peptides  to
     a protein (fastf3) or translated DNA (tfastf3) database.  Unlike the tradi-
     tional  fasta3  search,  which  uses  a protein or DNA sequence, fastf3 and
     tfastf3 work with a query sequence of the form:
	  >testf from mgstm1
	  MGCEN,
	  MIDYP,
	  MLLAY,
	  MLLGY
This sequence indicates that a mixture of four peptides has been found, with 'M'
in the first position of each one (as from a CNBr cleavage), in the second posi-
tion 'G', 'I', or 'L' (twice), at the third position 'C', 'D', or  'L'	(twice),
at the fourth position 'E', (included with the distribution), the mixture is de-
convolved to form:
     testf    MILGY-----------MLLEY-----------MGDAP-----------
	      :::::	      :::::	      :::::
     GT8.7  MPMILGYWNVRGLTHPIRMLLEYTDSSYDEKRYTMGDAPDFDRSQWLNEK
		    10	      20	30	  40	    50

     testf  --------------------------------------------------

     GT8.7  FKLGLDFPNLPYLIDGSHKITQSNAILRYLARKHHLDGETEEERIRADIV
		    60	      70	80	  90	   100

			   20
     testf  ------------MLCYN
			:::::
     GT8.7  ENQVMDTRMQLIMLCYNPDFEKQKPEFLKTIPEKMKLYSEFLGKRPWFAG
		   110	     120       130	 140	   150

Options
     fastf3  and  tfastf3 can accept a query sequence from the unix "stdin" data
     stream.  This makes it much easier to use fasta3 and its relatives as  part
     of  a WWW page. To indicate that stdin is to be used, use "-" or "@" as the
     query sequence file name.

     -b #   number of best scores to show (must be < -E cutoff)

     -d #   number of best alignments to show ( must be < -E cutoff)

     -D     turn on debugging mode.  Enables checks on	sequence  alphabet  that
	    cause problems with tfastx3, tfasty3, tfasta3.

     -E #   Expectation  value	limit for displaying scores and alignments.  Ex-
	    pectation values for fastf3 and tfastf3 are not as accurate as those
	    for the other fasta3 programs.

     -H     turn off histogram display

     -i     compare against only the reverse complement of the library sequence.

     -L     report long sequence description in alignments

     -m 0,1,2,3,4,5,6,10
	    alignment display options

     -n     force query to nucleotide sequence

     -N #   break long library sequences into blocks of # residues.  Useful  for
	    bacterial  genomes,  which	have  only  one sequence entry.  -N 2000
	    works well for well for bacterial genomes.

     -O file
	    send output to file

     -q/-Q  quiet option; do not prompt for input

     -R file
	    save all scores to statistics file

     -S #   offset substitution matrix values by  a constant #

     -s name
	    specify substitution matrix.  BLOSUM50 is used by  default;  PAM250,
	    PAM120,  and  BLOSUM62 can be specified by setting -s P120, P250, or
	    BL62.  With this version, many more scoring matrices are  available,
	    including  BLOSUM80  (BL80),  and  MDM_10, MDM_20, MDM_40 (M10, M20,
	    M40). Alternatively, BLASTP1.4 format scoring matrix  files  can  be
	    specified.

     -T #   (threaded,	parallel  only) number of threads or workers to use (set
	    by default to 4 at compile time).

     -t #   Translation table - tfastf3 can use  the  BLAST  tranlation  tables.
	    See http://www.ncbi.nih.gov/htbin-post/Taxonomy/wprintgc?mode=c/.

     -w #   line width for similarity score, sequence alignment, output.

     -x "#,#"
	    offsets query, library sequence for numbering alignments

     -z #   Specify statistical calculation. Default is -z 1, which uses regres-
	    sion  against the length of the library sequence. -z 0 disables sta-
	    tistics.  -z 2 uses the ln() length correction. -z 3  uses	Altschul
	    and Gish's statistical estimates for specific protein BLOSUM scoring
	    matrices and gap penalties. -z 4: an alternate regression method.

     -Z db_size
	    Set  the  apparent database size used for expectation value calcula-
	    tions.

     -1     Sort by "init1" score.

     -3     (TFASTF3 only) use only forward frame translations

Environment variables:
     FASTLIBS
	    location of library choice file (-l FASTLIBS)

     SMATRIX
	    default scoring matrix (-s SMATRIX)

     SRCH_URL
	    the format string used to define the option to re-search  the  data-
	    base.

     REF_URL
	    the  format  string  used to define the option to lookup the library
	    sequence in entrez, or some other database.

AUTHOR
     Bill Pearson
     wrp@virginia.EDU

				      local		       FASTF/TFASTFv3(1)

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