Nucleic acid sequence Nucleic acid sequence A nucleic acid sequence is a succession of letters that indicate the order of nucleotides forming alleles within a DNA (using GACT) or RNA (GACU) molecule. By convention, sequences are usually presented from the 5' end to the 3' end. For DNA, the sense strand is used. Because nucleic acids are normally linear (unbranched) polymers, specifying the sequence is equivalent to defining the covalent structure of the entire molecule. For this reason, the nucleic acid sequence is also termed the primary structure. The sequence has capacity to represent information. Biological deoxyribonucleic acid represents the information which directs
Homogentisic acid Homogentisic acid Homogentisic acid (2,5-dihydroxyphenylacetic acid) is a phenolic acid usually found in "Arbutus unedo" (strawberry-tree) honey. It is also present in the bacterial plant pathogen "Xanthomonas campestris pv. phaseoli" as well as in the yeast "Yarrowia lipolytica" where it is associated with the production of brown pigments. It is oxidatively dimerised to form hipposudoric acid, one of the main constituents of the 'blood sweat' of hippopotamuses. It is less commonly known as melanic acid, the name chosen by William Prout. Accumulation of excess homogentisic acid and its oxide, named alkapton, is a result of the failure of the enzyme