A new thermodynamic database for normal and modified nucleic acids has been developed. This Thermodynamic Database for Nucleic Acids (NTDB) includes sequence, structure and thermodynamic information as well as experimental methods and conditions. In this release, there are 1851 sequences containing both normal and modified nucleic acids. A user-friendly web-based interface has been developed to...

The technique of fast atom bombardment mass spectrometry has been shown to be capable of producing molecular weight and useful fragmentation information from a selection of penicilloic acids. In addition, the technique has been shown to give similar information on alkali metal salts of penicilloic acids.

Class separation of methylated free bile acids from bile acids conjugated with taurine and methylglycine was accomplished using a solvent system of 2,2,4-trimethylpentane-absolute ethanol 10:1 (v/v). By developing a silica thin-layer plate two times with solvent in a Brinkmann sandwich tank, the difficult resolution between methyl cholate and methyl glycolithocholate was achieved. Evidence is p...

The etiology and treatment of mood disorders has not yet been elucidated. Omega (omega)-3 fatty acids are essential fatty acids, which cannot be synthesized in the human body. Eicosapentanoic acid (EPA) and docosahexaenoic acid (DHA) are representative omega-3 fatty acids which are found in fish (eg., mackerel, herring, Chinook salmon) and vegetables (eg., flax, walnut, canola). The peripheral ...

Many bacteria can degrade a variety of proteins and utilize the resulting peptides and amino acids to synthesize their own cellular components. They can also catabolize amino acids as a means of providing some of the energy (ATP) needed for cellular function. Microorganisms vary from species to species with regard to their proteolytic ability, so these features can be useful when characterizing...

The aim of this paper is 2-fold. (1) To propose the use of a group of mathematical techniques, called clustering, in the elucidation of complex metabolic relationships. (2) To apply clustering for the identification of related groups of saturated fatty acids having a common metabolic pathway for their biosynthesis in the milk fat of lactating goats. In this way, four groups of branched-chain fa...

To recognize the DNA sequence and mine the hidden information to achieve the classification of organisms are viewed as a difficult work to biologists. As we know, the amino acids are the basic elements to construct DNA. Hence, if the codon usage of amino acids can be analyzed well, the useful information about classification of organisms may be obtained. However, if we choose too many amino aci...

The Bioinformatics Links Directory is an online community resource that contains a directory of freely available tools, databases, and resources for bioinformatics and molecular biology research. The listing of the servers published in this and previous issues of Nucleic Acids Research together with other useful tools and websites represents a rich repository of resources that are openly provid...

Signature lipid biomarker (SLB) analysis is a useful tool for identifying microorganisms and characterizing microbial communities in natural systems. Specific fatty acids, especially phospholipids (PLFA), are essential membrane components, make up a relatively constant proportion of the microorganisms under natural conditions and their patterns provide insight into the bacterial and fungal comm...