دورية
In vivo conversion of L-serine to D-alanine in a ribosomally synthesized polypeptide.
| العنوان: | In vivo conversion of L-serine to D-alanine in a ribosomally synthesized polypeptide. |
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| المؤلفون: | Skaugen, M, Nissen-Meyer, J, Jung, G, Stevanovic, S, Sletten, K, Inger, C, Abildgaard, M, Nes, I F |
| المصدر: | Journal of Biological Chemistry; November 1994, Vol. 269 Issue: 44 p27183-27185, 3p |
| مستخلص: | In the course of characterizing the bacteriocin lactocin S and its encoding gene, we discovered three alanine-for-serine substitutions which, apparently, is a violation of the genetic code. Subsequent chiral analysis of lactocin S hydrolysates revealed a correlation between D-alanine content and the three substitutions, implying a conversion of L-serine to D-alanine in lactocin S maturation. In order to explain this observation, we suggest a sequence of events initiated by the dehydration of serine, which is common in the biosynthesis of the lanthionine-containing polycyclic lantibiotics (Schnell, N., Entian, K.-D., Schneider, U., Götz, F., Zähner, H., Kellner, R. & Jung, G. (1988) Nature 333, 276-278; Jung, G. (1991) Angew, Chem. Int. Ed. Engl. 30, 1051-1068; Bierbaum, G. & Sahl, H.-G. (1993) Zentralbl. Bakteriol. 278, 1-22) and completed by the stereospecific reduction of dehydroalanine residues. The occurrence of non-lanthionine alpha-carbon stereoinversion in lactocin S maturation substantiates the hypothetical alpha-epimerization scheme originally put forward by Bycroft (Bycroft, B. W. (1969) Nature 224, 595-597), and we propose a revision of this model to accommodate the lactocin S-type stereoinversion. Lactocin S is the first prokaryotic exception to the rule that only L-amino acids are included in ribosomally synthesized peptides. |
| قاعدة البيانات: | Supplemental Index |
| تدمد: | 00219258 1083351X |
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| DOI: | 10.1016/S0021-9258(18)46966-9 |