Carbon trioxide

Abstract

Of the oxides of carbon, a molecular species with the formula CO3, rightly named carbon trioxide, is an unusual compound and was recently isolated and characterized by Moll, Clutter, and Thompson (1) using a matrix isolation technique. It was first postulated by Katakis and Taube (2) in 1962 as a kinetic intermediate to account for the observed rapid exchange between O and C02.The ultraviolet photolysis of C02 intrigued chemists for a long time and has contributed in no small measure its share of the "blame-the-walls" for all the experimental and theoretical difficulties. Fortunately, how-CHronological Survey of CO3 Investigations Year Experimental Evidence for COi and Related Ionic Species 1957 Observed a band at 1615 cm-1 in the combustion reaction of CO in Oj and interpreted it as arising from C03. 1960 Reported detection of CO3+ as a secondary ion in a mass spectrometer. 1962 Postulated an unstable kinetic intermediate in the exchange of oxygen between C02 and 0(JD). 1964 Postulated metastable species in C02 photolysis at 1600 A. 1964 Reported detection of COa in a reaction between CO and electronically excited 0 atoms. 1966 Postulated reactive species in the photolysis of COs at 1470 A. 1966 Postulated reactive species in the photolysis of CO2 at 1236 A. 1966 Preparation and characterization at 77 °K by infrared spectroscopy and isotope labeling. 1966 Collected mass spectral evidence from electron bombardment of carbonate esters in gas phase for the corresponding triphly protonated species, C(OH)3 +. 1965 Mass spectral detection ofCO3-ion in the plasma obtained in the r.f. discharges in C02, CO and 02. This observation could not be confirmed by Evans and Jennings ( 16).

Bacillus subtilis YxaG is a novel Fe‐containing quercetin 2,3‐dioxygenase

“…An analysis of the Bacillus subtilis genome revealed the presence of three genes that encode hypothetical proteins that belong to the bicupin family of proteins [1^3]. The bicupins are a subset of the cupin superfamily, which are de¢ned by a L-barrel protein domain structure and a well but not strictly conserved motif; G(X) 5 HXH(X) 3À4 E(X) 6 G followed by G(X) 5 PXG(X) 2 H(X) 3 N [3]. What sets the bicupins apart from the rest of the superfamily is the duplication of the protein domain and cupin motif within the polypeptide sequence.…”