Gblocks is an alignment curation tool which eliminates poorly aligned positions and divergent regions of an alignment of DNA or protein sequences.

Installation
First download the software from http://molevol.cmima.csic.es/castresana/Gblocks.html. The latest version at the time of this writing is Gblocks_Linux_0.91b.tar.Z.

$ zcat Gblocks_Linux_0.91b.tar.Z | tar xvf -
$ cd Gblocks_0.91b
$ sudo mv Gblocks /usr/local/bin
$ sudo chmod 755 /usr/local/bin/Gblocks

To use Gblocks, simply type Gblocks in the commandline.