USING NMRVIEW

TABLE OF CONTENTS

DISPLAY MODES

INTERRUPTING CONTOUR PLOTS

CURSORS

CURSOR CORRELATION

PEAK PICKING

PEAK DISPLAY

INTERACTIVE PEAK EDITING

KEYPAD NAVIGATION

DATABASE

USING MOLECULAR STRUCTURES

DISPLAY MODES

Most parameters effecting the display mode of spectra are specified in the spectral attributes panel. Spectra may be displayed as 1D vectors or as 2D slices. The 1D vectors can be displayed in a horizontal orientation (1Dx) or a vertical orientation (1Dy). These display modes (1Dx, 1Dy, and 2D) are selected with the pull down choice in the spectral attributes window. Also, in 2D contour plot mode you can display a 1D vector slice superimposed on the contour plot (seed 2D mode below).

In mode 1Dx, the two x values specify the plot limits of the vector. The y, z and z2 values specify the particular vector in the 2,3 or 4D matrix. If a range of values is specified for y, z or z2, all the vectors between those values will be drawn. In mode 1Dy, the two y values specify the plot limits of the vector. The x, z and z2 values specify the particular vector in the 2,3 or 4D matrix. In the 1D modes the value specified in the Scale entry, specifies the intensity difference between the maximum and minimum axes. The value specified in the Zero entery, specifies the point (as a fraction from zero to one, at which a value with intensity zero will be displayed. For example, in mode 1Dx, with Scale set to 100 , and Zero set to 0.5, the the y-axis range is from -50 to +50. With Scale set to 100, and Zero set to 0.0, the y-axis range is from 0 to 100.

In 2D mode the spectra are displayed as contour plots. The panel entry, Level, specifies the intensity of the lowest contour that will be drawn. The panel entry, LvlMul, specifies the ratio of intensities of subsequent contours. The panel entry, #Lvls, specifies the maxinum number of contours to display. The x values specify the plot limits along the x-axis. The y values specify the plot limits along the y-axis. In 2D mode "real-time" slices can be displayed that track the position of crosshair cursor 1 (the black crosshair). Slices can be in the x, y, z or (z2 NOT YET) dimension of the spectrum. X and Z slices are drawn parallel to the X axis of the window. Y and Z2 slices are drawn parallel to the Y axis of the window. The slice is continuously updated as the cursor is moved.

For 3 and 4D spectra the specific planes to be drawn are specified with the z and z2 (for 4D spectra) values. If a range of values for z and/or z2 are specified, all planes between the two specified values (inclusive) are drawn. The file dimensions and the display dimensions can correspond in any desried manner. The pull down choice box following the x and ydisplay entries is used to specify which dataset dimension is specified on the particular axis.

INTERRUPTING CONTOUR PLOTS

To interrupt a contour plot in progress, place the mouse pointer in the window from which NMRView was started, and press ctrl-C. The plotting should stop shortly.

CURSORS

Each spectral window may have two crosshair cursors. Clicking the LEFT mouse button in a spectral window displays cursor 1, which is generally colored black. Clicking the MIDDLE mouse button in a spectral window displays cursor 2, which is generally colored red. Cursor 1 may be moved by pointing the mouse cursor near the vertical or horizontal lines of the crosshair, pressing the LEFT mouse button and dragging the cursor to the desired position. The vertical and horizontal lines of the cursor may be moved independently. The cursor lines only move if the mouse button is depressed when the mouse cursor is within 1/2 inch of the cursor line. To move both lines of the cursor press the mouse button down when the cursor is near the intersection of the two lines. Cursor 2 is moved in an analagous fashion by pressing the MIDDLE mouse button and dragging the cursor.As the cursors move, the current position of both cursors is displayed in ppm at the top of the window. The color of the position display is the same as the color of the corresponding cursor. The difference between the two cursor posiions in Hz is also displayed.

CURSOR CORRELATION

The cursors in different windows automatically track each other in what is generally an appropriate manner. No commands are required to start correlated cursor tracking. Cursor correlation is dependent on the label given to each axis of the spectrum during the referencing process. For example, consider the case where 5 windows are open, with axis labels as indicated below.

Window-Name X-axis-Label Y-axis-Label

a 15N 1HN

b 13C 15N

c 1H1 1H2

d 1HN 13C

e 15N 1HN

If a vertical crosshair moves in window "a", the horizontal crosshair of window "b" and the vertical crosshair of window "e" will move. If the horizontal crosshair of window "a moves, the vertical crosshair of window "d" and the horizontal crosshair of window "e" will move.The cursor in each window only tracks the motion of the moved cursor if the plot limits of the window overlap the position of the moved cursor. Cursor tracking can be disabled in a window by changing the window's axis label(s).

PEAK PICKING

To pick peaks in a particular region of the spectrum, display the region in any spectral window. Then choose PeakPick from that window's pop-up menu. The PeakPick Control Window will appear. Type the name that you wish to be associated with the new peaklist in the text field of the control window. Click on the Pick button to start the automatic peakpicking. As peaks are identified in the spectrum, boxes annotated with the peak number will be drawn on the spectrum at the position of each identified peak. The boxes will be drawn in either the color green or the color red. The peaks that are boxed in red violate some criteria. Peaks that are too narrow or are too wide will be red. The minimum and maximum width criteria can be set for each dimension in the PeakPick Control Window. At present, these criteria are specified in units of data points. Peaks that are on the edge of the spectrum will also be colored red. Peaks that violate any of these three criteria will be stored in the peak list, but the error field associated with each peak dimension will denote the violation with the symbols N, W, or E (for narrow, wide, or edge).

Some spectra, especially 3D and 4D spectra, may be collected with a sweep width narrower than the frequency range of the spectral peaks. In these spectra, peaks are folded to a position that differs from their true position by an integer multiple of the sweep width. Peaks on the edge of such spectra "wrap" arround to the opposite edge. To properly pick spectra with such wrapped peaks, check the Fold box in the PeakPick Control Window for the desired dimension(s). When Fold is selected the peakpicker will wrap at the edge of the spectrum so that the peak width and position are properly determined.

To pick peaks in a specified region of the spectral window, place the crosshair cursors so as to box in the desired region. Select the Box attribute in the PeakPick Control Window. Now, only the region within the box will be analyzed for peaks. To pick peaks in the entire window select the Window attribute instead.The peaks that are picked may be stored as a new peak list, they may replace an existing peak list, or they may be appended to an existing peak list. The desired option may be selected from the pulldown list that specifies the New, Replace, or Append Attributes.

PEAK DISPLAY

Peaks in the peak lists may be displayed on spectra in a variety of ways. The first method is to select the Showpeaks entry from the spectral windows pop-up menu. This will result in the display of peaks from the peak list currently selected in the Peak Analysis Window. The peaks will be drawn as rectangular boxes centered on the peak position. The boxes are labelled in the upper right corner. By default the label is the peak number, but this can be changed to display atom and/or residue information with the win -peak_lab_type command. With 3D and 4D spectra, only peaks whose z and/or z2 dimensions are within a specified number of planes of the planes currently displayed will appear. The range within which planes are displayed is specified with the win -peak_off command. Peaks whose z and/or z2 dimensions are closest to the display plane appear with the color red. Those peaks that are off the display planes, but within the specified range appear with the color green. These colors may be changed with the win -peak_col_on and win -peak_col_off commands. Alternatively, the color choice may be based on whether the peak has been assigned (defined as the lack of a ? in the peak label fields). This option may be selected with the win -peak_col_type command.

The second method to display peaks is by selecting the desired peak list name from the Display Peaks pull-down list in the Spectral Attributes Window. If a peak list is selected in this pull-down list, that peak list will be automatically displayed whenever the window is redrawn. It will also appear on hard-copy plots. All peak display options operate as described in the previous paragraph.

Finally, peaks can be displayed using the command, win -showpeaks. This is equivalent to selecting the Showpeaks entry in the spectral display pop-up window.

INTERACTIVE PEAK EDITING

The position and size of peaks can be edited interactively using the mouse. To change the position of a peak, point to the center of the peak with the mouse. While holding the Left Shift Key down, press the left mouse button down. Now, while keeping the left mouse button down you can drag the peak around the screen to its new position. Editing the bounds of the peak is done in a similar manner using the middle mouse button. Point to the center of the peak. While holding the Left Shift Key down, press the middle mouse button down. Now, while keeping the middle mouse button down you can drag the corner of the peak box around to its new position. Don't be alarmed when the peak shrinks to a point when you first press the mouse button down. This is normal, simply drag the peak bounds back out to the desired size. To interactively delete a peak, point to the center of the peak, hold the Left Shift Key down, and double click the left mouse button.

KEYPAD NAVIGATION

You can quickly navigate around spectra and peak-lists using keys on the auxilliary keypads of the keyboard. To use this feature the cursor must be in the active window.

NUMERIC KEYPAD
Use the numeric keypad to zoom and pan the spectrum as follows.
1
Pan down and to the left.
2
Pan down.
3
Pan down and to the right.
4
Pan left.
5
Shift view to center on crosshair position.
6
Pan right.
7
Pan up and to the left.
8
Pan up
9
Pan up and to the right.
-
Zoom out.
+
Zoom in.
CURSOR KEYS
Use the cursor keys to move up or down planes in 3D and 4D spectra, or increment or decrement rows and columns in 1D displays of 2D,3D or 4D spectra.
Down Arrow
1Dx: Move up a row.

3D,4D Spectrum: Move Down a plane.

Up Arrow
1Dx: Move down a row.

3D,4D Spectrum: Move Up a plane.

Left Arrow
1Dy: Move left a column.

4D Spectrum: Move Down a Z2 plane.

Right Arrow
1Dy: Move right a column.

4D Spectrum: Move Up a Z2 plane.

PAGING KEYS
Use the Insert,Delete,Home,End,PageUp and PageDown keys to navigate peaklists.
Insert
Undelete the current peak.
Delete
Delete the current peak.
Home
Move to the first peak of current list.
End
Move to the last peak of current list.
PageUp
Move to the previous peak of current list.
PageDown
Move to the next peak of current list.

DATABASE

NMRView stores a variety of information in a database. By default this database is named "NMRView.gdbm". When NMRView starts up it will look for a file with this name. If it finds this file it will attempt to open it. If it doesn't exist in the current directory it will create an empty database named "NMRView.gdbm". The database can only be opened by one person at a time. The database is always kept current so that even if NMRView crashes all information stored in the database should reflect the information in memory at the time of the crash. A different database can be specified on the command line when NMRView is started. Included in the database are the peaklists, the chemical shift assignments, the molecular topology of any sequence currently in use, and the coordinates of any structures that have been read into NMRView. Development is ongoing to add additional features to the database.

USING MOLECULAR STRUCTURES

The best way to read a molecular structure into NMRView is to first read a sequence file in NMRView format (the same as that used by PEGASUS). A sequence file consists of a line for each residue, each line containing the three-letter code for the amino-acid. NMRView will try to find a corresponding residue in its residue library, (in the directory $NMRVIEWHOME/reslib) and read in the molecular topology. To read a sequence use the sread -seq command. The topology will be stored in the current database, and need not be read in again during future NMRView sessions. To read in molecular coordinates (after having read the topology) use the sread -xyz command to read xyz coordinates from files in the Brookhaven Protein Data Bank (PDB) format. The file will be scanned and coordinates of atoms whose name and residue number match an atom in the internal topolgy will be read in. These coordinates will also be stored in the current database, and need not be read in again during future NMRView sessions. Up to 100 structures can be read and stored in separate memory locations.