Inteins invading mycobacterial RecA proteins

Five new inteins were discovered in a survey of 39 mycobacterial strains th at was undertaken to clarify the role of RecA inteins in mycobacteria, They are all inserted at the RecA-b site of the recA gene of Mycobacterium chit ae, M. fallax, M. gastri, M. shimodei and M. thermoresistibile and belong t o the MleRecA allelic family. Sequence analysis showed that although only M . tuberculosis harbours an intein at the RecA-a site the sequence of the Re cA-b site is well conserved between species. Furthermore, the presence of i nteins does not correlate with specific characteristics of the species such as pathogenicity or growth rate. (C) 2000 Federation of European Biochemic al Societies. Published by Elsevier Science B.V. All rights reserved.