Abstract
SecA is a central component of the bacterial Sec preprotein translocase. Besides the housekeeping SecA (SecA1), some mostly pathogenic Gram-positive bacteria possess an accessory SecA (SecA2) that is involved in the export of a few substrates only. Here we show that neither of the two secA homologous genes present in the genome of the non-pathogenic bacterium Corynebacterium glutamicum can be deleted, unless a copy of the respective gene is provided in trans on a plasmid. This finding is in marked contrast to all other cases examined so far making C. glutamicum the first reported bacterium possessing two essential SecA proteins.
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Acknowledgments
We are very grateful to Astrid Bida for excellent technical assistance and H. Sahm for his continuous support. M. Caspers was supported by the Graduiertenkolleg GRK 57/3-03 “Molekulare Physiologie: Stoff- und Energieumwandlung”.
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Communicated by Arnold Driessen.
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Caspers, M., Freudl, R. Corynebacterium glutamicum possesses two secA homologous genes that are essential for viability. Arch Microbiol 189, 605–610 (2008). https://doi.org/10.1007/s00203-008-0351-0
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DOI: https://doi.org/10.1007/s00203-008-0351-0