Micrococcus hydroxylation

The anaerobe Peptococcus (Micrococcus) aerogenes had a dehydrogenase that carried out specific hydroxylation at the 6-positions of 2- and 8-hydroxypurine, and was therefore distinct from xanthine dehydrogenase from which it could be separated (Woolfolk et al. 1970). It was also able to carry out dismutation of 2-hydroxypurine to xanthine (2,6-dihydroxypurine) and hypoxanthine (6-hydroxypurine). 

Three of these saccharides have to be N-acetylmuramic acid, and are either A, C, and E, or B, D, and F. The choice is easy, because the hydroxyl group on C-3 of carbohydrate C points toward the cleft and is hydrogen-bonded to the ring-nitrogen atom of L-tryptophan at position No. 63 of the protein core hence, there is no space for the lactoyl side-chain of N-acetylmuramic acid. Consequently, B, D, and F are N-acetylmuramic acid residues, and this identification is consistent with the low-resolution results. The lactoyl side-chains point out of the cleft, so that there is room for a peptide tail, such as occurs in the cross-linking of the cell walls of Micrococcus lysodeikti-cus.Ui... 

The thiol group can also be found in heterocyclic compounds such as 2-mercaptobenzothiazole (9) and echinoclathrine C (10). Compound 9 was isolated from the symbiont bacterium Micrococcus sp., which was obtained from the sponge Tedania ignis [13]. The pyridine alkaloid echinoclathrine C (10) and its S-acetylated derivative, echinoclathrine B (11), were isolated from the Okinawan sponge Echinoclathria sp. [14]. The position of the hydroxyl and acylamino group on the phenyl ring in echinoclathrines (11 and 10) was recently corrected [15]. Compound 11 showed weak immunosuppressive activity in the mixed lymphocyte reaction assay with an IC50 of 9.7 pg/ml [14]. 

Muindi JRF, Sinha BK, Gianni L, Myers CE (1984) Hydroxyl radical production and DNA damage induced by anthracycline-iron complex. FEBS Lett 172 226-230 Mujica V, Nitzan A, Mao Y, Davis W, Kemp M, Roitberg A, Ratner MA (1999) Electron transfer in molecules and molecular wires geometry dependence, coherent transfer, and control. In Jortner J, Bixon M (eds) Electron transfer From isolated molecules to biomolecules. Part Two, Advances in Chemical Physics Series, Vol 107. Wiley, New York, pp 403-428 Mullenger L, Ormerod MG (1969) The radiosensitization of Micrococcus sodonensis by N-ethyl ma-leimide. Int J Radiat Biol 15 259-269... 

Hydroxylation of short chain aliphatic carboxylic acids can be accomplished by a number of micro-organisms (see also Scheme 3) including Endomyces reessii, Trichosporum fermentans, Torulopsis Candida and Micrococcus flavus. Longer chain carboxylic acids can also satisfactorily hydroxylat. ... 

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