Soaking in Cs2SO4 reveals a caesium‐aromatic interaction in bovine‐liver rhodanese

Abstract

On the basis of the analysis of mycolates, the type strain of Mycobacterium thamnopheos has been considered as a member of the genus Nocardia. In a comparative study conducted on mycobacterial species were found that M. thamnopheos synthesized two types of mycolate having the same mobilities on thin-layer chromatography as those of mycobacteria, but different from nocardiomycolates. Mass spectrometry analyzes showed that the major series of both types consisted of polyunsaturated mycolic acids, rainging from C72 to C78 with four or five double bonds. On pyrolytic mass spectrometry or gas chromatography, the least polar mycolates released mainly mono-unsaturated C22 esters whereas the other type yielded saturated C20 and C22 esters. THese results suggested that M. thamnopheos might be more related to the Aurantiaca toxon than to mycobacteria and Nocardia. The permanganate-periodate oxidation products of esters obtained by pyrolysis of the least polar mycolates showed that they contained docosen-4-oic and docosen-6-oic acids. Both types of mycolate esters yielded the same set of long-chain meroaldehydes on pyrolysis. These meroaldehydes were significantly distinct from those of mycobacterial mycolates in the location of the double bonds. After hydrogenation of the double bond located in the alkyl-branched chain, the two types of mycolates had the same mobility on thin-layer chromatography, indicating that the difference of migration was due to the additional double bond found in the least polar mycolates. Based on stereochemical data, the relative configuration of both mycolates was found to be threo, like that established for all mycolates studied so far.