Conserved non-coding sequence degenerate sequences with no biological function. An example of a pseudogene is the gene for L-gulonolactone oxidase, a liver enzyme necessary for biosynthesis of L-ascorbic acid (vitamin C) in most birds and mammals, but which is mutated in the haplorrhini suborder of primates, including humans which require ascorbic acid or ascorbate from food. The remains of this non-functional gene with many mutations is still present in the genomes of guinea pigs and humans. Ultraconserved regions (UCRs) are regions over 200 bp in length with 100% identity across species. These unique sequences are mostly found in noncoding regions. It is still
Chemistry of ascorbic acid performs the dual function of removing the two acetal groups and ring-closing lactonization. This step yields ascorbic acid. Each of the five steps has a yield larger than 90%. A more biotechnological process, first developed in China in the 1960s, but further developed in the 1990s, bypasses the use of acetone-protecting groups. A second genetically modified microbe species, such as mutant "Erwinia", among others, oxidises sorbose into 2-ketogluconic acid (2-KGA), which can then undergo ring-closing lactonization via dehydration. This method is used in the predominant process used by the ascorbic acid industry in China, which supplies 80% of world's ascorbic