![]() ![]() tannophilus and other yeast species, such as the workhorse Saccharomyces cerevisiae, Riley noted.īeyond its potential effects on this and other biotech applications, CUG alanine coding might change the way scientists consider codon and transfer RNA (tRNA) evolution. tannophilus with either a wild-type or CUG-replaced, hygromycin –resistance gene, only the yeasts with the altered selection gene grew on antibiotic plates.Ĭodon modification may be required for researchers using yeast to express novel proteins in P. They found 178 identifiable peptides that mapped to coding sequences containing CUGs 90 percent of them had LC-MS peaks indicating alanine and only 9 percent of the spectrum implied leucine. ![]() tannophilus grown in culture and analyzed them using liquid chromatography mass spectrometry (LC-MS). To determine which amino acid was actually present in the proteins, Riley and colleagues extracted peptides from P. tannophilus the standard coding occurred only 7 percent of the time, instead aligning 25 percent with alanine, the researchers reported. “It’s sort of a footprint of what the organism is using that codon for,” study coauthor Robert Riley, a bioinformatician at the JGI, told The Scientist.įor most species studied, CUG coded for conserved leucine between 70 percent and 86 percent of the time, but for P. Because the change is at the level of translation, researchers needed to compare sequences and codon usage across species to identify this hidden variation.Īs part of a large phylogenetic study, researchers at the US Department of Energy’s Joint Genome Institute (JGI) in Walnut Creek, California, and their colleagues studied the alignment of predicted proteins in 700 orthologous genes from 29 different yeasts in an effort to identify conserved amino acids and determine which codons they came from. Replacing bulky hydrophobic leucine with alanine or serine-both small, polar amino acids-could disrupt the structures and functions of critical proteins. Santos, who has studied the CUG-serine reassignment extensively, told The Scientist that while a coding change may eventually confer an evolutionary fitness advantage, the initial reassignment comes at a substantial cost. “For this event to happen twice in a different linage is unexpected,” said Manuel Santos, the director of the Institute for Biomedicine at the University of Aveiro, Portugal, who was not involved with either study.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |