A phylogenomic profile of globins

摘要: Globins occur in all three kingdoms of life: they can be classified into single-domain globins and chimeric globins. The latter comprise the flavohemoglobins with a C-terminal FAD-binding domain gene-regulating globin coupled sensors, variable domains. encompass sequences related to «truncated» hemoglobins 2-over-2 instead canonical 3-over-3 α-helical fold. A census 26 archaeal, 245 bacterial 49 eukaryote genomes was carried out. Only ~25% archaea have globins, including single From one seven per genome were found ~65% genomes: presence number are positively correlated size. appear mostly absent Bacteroidetes/Chlorobi, Chlamydia, Lactobacillales, Mollicutes, Rickettsiales, Pastorellales Spirochaetes. Single metazoans fungi, diplomonads mycetozoans. Although red algae green ciliates only Plants symbiotic nonsymbiotic hemoglobins. Over 90% eukaryotes globins: nematode Caenorhabditis has most putative ~33. No parasitic, unicellular such as Encephalitozoon, Entamoeba, Plasmodium Trypanosoma. Bacteria types Archaeado not Eukaryotes lack sensors. Since organisms other than animals enzymes or it is likely that evolution an oxygen transport function accompanied emergence multicellular animals.