
                                  findkm 



Function

   Find Km and Vmax for an enzyme reaction

Description

   Takes a file of enzymatic data and plots Michaelis Menten and Hanes
   Woolf plots of the data. From these it calculates the Michaelis Menten
   constant (Km) and the maximum velocity (Vmax) of the reaction.

Usage

   Here is a sample session with findkm


% findkm -graph cps 
Find Km and Vmax for an enzyme reaction
Enzyme kinetics data (application-specific) file: enztest.dat
Output file [enztest.findkm]: 

Created findkm.ps

   Go to the input files for this example
   Go to the output files for this example

Command line arguments

   Standard (Mandatory) qualifiers:
  [-infile]            infile     Enzyme kinetics data (application-specific)
                                  file
  [-outfile]           outfile    [*.findkm] Output file name
   -graphlb            xygraph    [$EMBOSS_GRAPHICS value, or x11] Graph type
                                  (ps, hpgl, hp7470, hp7580, meta, cps, x11,
                                  tekt, tek, none, data, xterm, png, gif)

   Additional (Optional) qualifiers: (none)
   Advanced (Unprompted) qualifiers:
   -[no]plot           boolean    [Y] S/V vs S

   Associated qualifiers:

   "-outfile" associated qualifiers
   -odirectory2        string     Output directory

   "-graphlb" associated qualifiers
   -gprompt            boolean    Graph prompting
   -gdesc              string     Graph description
   -gtitle             string     Graph title
   -gsubtitle          string     Graph subtitle
   -gxtitle            string     Graph x axis title
   -gytitle            string     Graph y axis title
   -goutfile           string     Output file for non interactive displays
   -gdirectory         string     Output directory

   General qualifiers:
   -auto               boolean    Turn off prompts
   -stdout             boolean    Write standard output
   -filter             boolean    Read standard input, write standard output
   -options            boolean    Prompt for standard and additional values
   -debug              boolean    Write debug output to program.dbg
   -verbose            boolean    Report some/full command line options
   -help               boolean    Report command line options. More
                                  information on associated and general
                                  qualifiers can be found with -help -verbose
   -warning            boolean    Report warnings
   -error              boolean    Report errors
   -fatal              boolean    Report fatal errors
   -die                boolean    Report dying program messages

Input file format

   The input file is a file of enzymatic data, [S] against V, Substrate
   concentration against reaction velocity.

  Input files for usage example

  File: enztest.dat

  0.10   2
  0.20   4
  0.50   9
  1.00  17
  2.00  29
  5.00  50
 10.00  67
 20.00  80
 50.00  91
100.00  95

Output file format

  Output files for usage example

  File: enztest.findkm

---Hanes Woolf Plot Calculations---
Slope of best fit line is a = 0.01
Coefficient in Eqn of line y = ma +b is b = 0.05
Where line cuts x axis = (-0.20, 0)
Where line cuts y axis = (0, 0.05)
Limit-point of graph for plot = (103.00, 1.08)

Vmax = 99.70, Km = 4.894611

  Graphics File: findkm.ps

   [findkm results]

Data files

   None.

Notes

   None.

References

    1. Voet & Voet (1993) 'Biochemistry'
    2. Dawes 'Quantitative Problems in Biochemistry' 5th Edition.
    3. Manuel G. Claros, Francisco M. Canovas 'Lines&Kinetics: a graphic
       tool to deal with linear regressions and enzyme kinetics.'
       EMBnet.news vol 5.1
       http://www.uk.embnet.org/embnet.news/vol5_1/kinetics.html
    4. Cornish-Bowden (1996) 'Fundamentals of Enzyme kinetics' Portland
       Press, London.

Warnings

   None.

Diagnostic Error Messages

   None.

Exit status

   It exits with a status of 0.

Known bugs

   None.

See also

   Program name Description

Author(s)

   Sinead O'Leary (current e-mail address unknown)
   while she was at:
   HGMP-RC, Genome Campus, Hinxton, Cambridge CB10 1SB, UK

   This application was modified by David Martin
   (dmartin © rfcgr.mrc.ac.uk)

History

   Completed November 1999

   Modified May 2000

Target users

   This program is intended to be used by everyone and everything, from
   naive users to embedded scripts.

Comments

   None
