Biomaterial Database

An Orphan Riboswitch Unveils Guanidine Regulation in Bacteria. 2017

Wendy W K Mok, and Mark P Brynildsen

Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA.

In this issue, Nelson and colleagues (2017) determined that guanidine, the prevalent protein denaturant, is the long-lost ligand sensed by the ykkC class of riboswitches, and identified that members of its regulon are involved in guanidine detoxification and export.

UI	MeSH Term	Description	Entries
D006146	Guanidines	A family of iminourea derivatives. The parent compound has been isolated from mushrooms, corn germ, rice hulls, mussels, earthworms, and turnip juice. Derivatives may have antiviral and antifungal properties.
D001419	Bacteria	One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.	Eubacteria
D012329	RNA, Bacterial	Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.	Bacterial RNA
D058928	Riboswitch	Part of a MESSENGER RNA molecule that undergoes a conformation change upon binding a specific metabolite or other small molecule thereby regulating the messenger RNA's transcription, post-transcriptional processing, transport, translation, or stability in response to varying levels of the metabolite or other small molecule.	Riboswitches,Ribosensor,Ribosensors
D019791	Guanidine	A strong organic base existing primarily as guanidium ions at physiological pH. It is found in the urine as a normal product of protein metabolism. It is also used in laboratory research as a protein denaturant. (From Martindale, the Extra Pharmacopoeia, 30th ed and Merck Index, 12th ed) It is also used in the treatment of myasthenia and as a fluorescent probe in HPLC.	Guanidine Hydrochloride,Guanidinium,Guanidinium Chloride,Guanidine Monohydrate,Guanidine Monohydrobromide,Guanidine Monohydrochloride,Guanidine Monohydroiodine,Guanidine Nitrate,Guanidine Phosphate,Guanidine Sulfate,Guanidine Sulfate (1:1),Guanidine Sulfate (2:1),Guanidine Sulfite (1:1),Guanidium Chloride,Chloride, Guanidinium,Chloride, Guanidium,Hydrochloride, Guanidine,Monohydrate, Guanidine,Monohydrobromide, Guanidine,Monohydrochloride, Guanidine,Monohydroiodine, Guanidine,Nitrate, Guanidine,Phosphate, Guanidine,Sulfate, Guanidine