DNA Strider
A bit dated but still great full featured sequence manipulation application for the mac. Freeware

Amplify v1.2
This software is for use in designing, analyzing, and simulating experiments involving the polymerase chain reaction (PCR). Given a template sequence and two primers, it will predict the possible outputs of the PCR, taking into account also weak matches to the target sequence. Freeware, thanks to Bill Engels

DNAid v1.8
As the author says, 'DNAid is not a heavyweight package which will run your 'just-sequenced gene' through every prediction or analysis algorithm in the known universe.' However, it is a very usefull application that allows to perform all the basic manipulations of DNA sequences such as restriction mapping, translation, reverse-complement and others. Freeware, thanks to Frédéric Dardel

MacPlasmap v1.8.2
It draws, stores, and prints high-quality circular plasmid maps with the data you specify. Fully functional. Shareware! Please read the enclosed documents before using the application

Primers! v1.0
Primers! is a very popular Macintosh utility to aid scientists in picking precisely the PCR oligos which fit their needs.Imput the target sequence and a range of selection, and Primers! will sugest the best PCR primers to amplify the selected region. Shareware at your discretion, thanks to Richard J. Resnick (Apple Pi Software). Please read the 'Read Me' file before using the application. Requires any Macintosh with a Color monitor and System 7 or beyond.

RasMac v2.6
RasMac is the Mac version of RasMol, a molecular graphics freeware program intended for the visualisation of proteins, nucleic acids and small molecules, written by Roger Sayle.You can downlod structural coordinates for a molecule of your choice -FOR INSTANCE HERE-and view, rotate and customize the look of the molecule right on your Mac even with no structural biology background (Thank you Roger Sayle!). Great for educational purposes. An excellent web site maintained by Eric Martz, for download and informations on RasMol and CHIME, a RasMol version designed as browser plug-in, can be found HERE. Before using RasMac, please read the enclosed 'Notice' file

SeqView v1.0.1
SeqVu is an alignment editor with analysis options that allows you to work quickly and simply with multiple sequences. It is ideal for manually correcting and obtaining publication-quality pictures from alignments produced using alignment software such as ClustalV or GCG pileup. Fully functional. Shareware.

Speakquencer v1.4
Speakquencer is a tool for entering and/or verifying nucleotide or amino acid sequence information. The application reads pre-existing sequences or speaks sequence as it is entered form the keyboard. Freeware, thanks to Christian Fritze

Swiss-PdbViewer 4.1 (Macos, Linux, Windows)
Free Molecular visualization software by Nicolas Guex and Manuel C. Peitsch. Swiss-PdbViewer is an application that provides a user friendly interface allowing to analyse several proteins at the same time. The proteins can be superimposed in order to deduce structural alignments and compare their active sites or any other relevant parts. Amino acid mutations, H-bonds, angles and distances between atoms are easy to obtain thanks to the intuitive graphic and menu interface. For informations, tutorials, and to download the viewer for other platforms (PC, SGI, Linux) visit the Swiss PdbViewer official site at expasy.