From chemistry-request: at :ccl.net Thu Sep 30 12:26:15 2004 Received: from www.eyesopen.com (eyesopen.com [208.41.78.163]) by server.ccl.net (8.12.8/8.12.8) with ESMTP id i8UHQEsR010563 for ; Thu, 30 Sep 2004 12:26:14 -0500 Received: from eyesopen.com (208-41-78-162.client.dsl.net [208.41.78.162]) (authenticated) by www.eyesopen.com (8.11.6/8.11.6) with ESMTP id i8UGmv717189 for ; Thu, 30 Sep 2004 10:49:01 -0600 Message-ID: <415C443E.2050507!at!eyesopen.com> Date: Thu, 30 Sep 2004 11:37:02 -0600 From: George Vacek Organization: OpenEye Scientific Software User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.0.2) Gecko/20030208 Netscape/7.02 X-Accept-Language: en-us, en MIME-Version: 1.0 To: chemistry!at!ccl.net Subject: QUAC PAC 1.1 - quality charge states and charges of small molecules and proteins Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, hits=0.8 required=7.5 tests=MY_DSL autolearn=no version=2.61 X-Spam-Checker-Version: SpamAssassin 2.61 (1.212.2.1-2003-12-09-exp) on servernd.ccl.net OpenEye announces the release of QUAC PAC 1.1, a suite of programs that generates high-quality charge states and charges for both small molecules and proteins. QUAC PAC offers everything necessary to do charges right. It includes pKa state and tautomer enumeration in order to get correct protonation states, partial charges using multiple models that cover a range of speed and quality, and electrostatic potential map construction and storage. QUAC PAC's highest quality partial charges are obtained for ligand molecules using the AM1-BCC model, designed to reproduce HF/6-31G* quality charges at about 1 molecule per second for drug-sized molecules. For screening purposes, QUAC PAC also offers the VC2003 and MMFF partial charges models, which can process about 400 and 1000 molecules per second, respectively. QUAC PAC's enumerates all reasonable pKa and tautomeric states, ensuring that they will be in the ensemble for subsequent screens. For proteins, QUAC PAC determines pKa via Poisson-Boltzmann (PB) electrostatics. One of the most novel components of QUAC PAC is the ability to handle PREPS (Polynomial Representation of Electrostatic Potential Surfaces). PREPS is a compact method of storing through-space potential distributions, in a 184-character string, so that they may be attached to any molecule's structure file so that it can be quickly used on the fly, rather than having to be recalculated. For further information, please visit www.eyesopen.com or contact business!at!eyesopen.com. Regards, George Vacek VP, Business Development OpenEye Scientific Software