This program computes, for a nucleic acid duplex, the enthalpy, the entropy and the melting temperature of the helix-coil transitions. Three types of hybridisation are possible: DNA/DNA, DNA/RNA, and RNA/RNA. The program first computes the hybridisation enthalpy and entropy from the elementary parameters of each Crick's pair by the nearest-neighbor method. Then the melting temperature is computed. The set of thermodynamic parameters can be easely changed, for instance following an experimental breakthrough. MELTING is a free program (free as in freedom). Its source code is open, and you can get MELTING from here for free. MELTING 4 is written in ISO C and MELTING 5 in Java. It can be compiled on any operating system. Some perl scripts are provided for MELTING 4 to show how melting can be used as a block to construct more ambitious tools.

The current stable version is v5.0.3. MELTING 5 has been rewritten from the beginning in Java (1.5) and provides a large set of thermodynamic models to compute the enthalpy and entropy of several structures in the duplex : perfectly matching sequences, single mismatch, tandem mismatch, internal loop, single dangling end, second dangling end, long dangling end (only one to four poly A), single bulge loop, long bulge loop, inosine base (I), hydroxyadenine (A*), azobenzene (cis X_C and trans X_T), locked nucleic acids (Al, Gl, Tl, Cl). MELTING 5 can manage a fourth type of hybridization : 2-o-methyl RNA/RNA. A lot of new ion corrections are available for Sodium, Magnesium, Potassium, Tris concentrations. The algorithm of Owczarzy et al is used to determine which correction to apply (see the MELTING 5 documentation for further information). New approximative formulas are available and to take into account the magnesium, tris and potassium concentrations, a sodium equivalent concentration is determined before computing the melting temperature with one of the approximative formulas. Some formulas are also available to correct the melting temperature when DMSO and formamide are present. The MELTING predictions accuracy has been improved in the 5 version, mostly for self complementary sequences. See the html version of the documentation for more information.

• The MELTING 4.3 distribution contains the program sources, binaries for Linux 32 bits, Linux 64 bits, Windows and MacOS, a GUI interface written in Perl/Tk, a perl script to run MELTING on multiple sequences, another to run iteratively MELTING along a nucleic acid by sliding a window of a specified width, the full documentation in several formats (PDF, HTML), a bunch of thermodynamic data tables and a benchmark of experimentally measured Tm.
• The MELTING 5.0.3 distribution contains the JAR file of the program with some scripts to run dirctly the program on unices and Windows systems, the java source code, the Javadoc, the full documentation in several formats (PDF, HTML, PS, TXT, DVI), a bunch of thermodynamic data tables and examples of computed melting temperature in comparison to experimentally measured Tm.
• The same distributions can also be found in sourceforge.net.
• ChangeLog
• MELTING is licensed under the GNU General Public License. That limits your right to restrict the rights of others! In particular:
  • If you distribute MELTING, you have to distribute its sources as well, or add a reference to the present web-site in your documentation.
  • If you use MELTING source-code in a program, this program HAS TO BE released under the GNU General Public License.
  • If you use MELTING as an invisible module of your program, behind a common interface, this program HAS TO BE released under the GNU General Public License.
• WWW MELTING 4.3 interface at the EBI.
• WWW interface at the Pasteur Institute.
• SOAP Server providing programmatic access to our implementation of MELTING over the web.
• A Graphical interface written in perl/tk. is available for MELTING 4. screenshot. Of course, you need Perl and Perl/Tk on your machine. Users of unix-like OS can easily find those programs on their distribution. For Win32 users, Perl distributions containing Tk can be find at ActiveState. Note that in this case, Tk is not installed by default.
• MELTING 5.0.3 HTML version of the manpage.
• MELTING 4.3 HTML version of the manpage.
• Mailing-list devoted to MELTING.
• The archives of the mailing-list.
• Debian packages melting.
• Ubuntu packages melting.

Le Novère N. (2001). MELTING, computing the melting temperature of nucleic acid duplex. Bioinformatics, 17: 1226-1227.
(PDF version)

Softwares using MELTING 4

• OligoDB
• SOL
• SEPON
• siRNA