Agnieszka SEKOWSKA
EDUCATION
RESEARCH AND PROFESSIONAL EXPERIENCE
December 1999-March 2000:
Post-doctoral Fellowship in Unité de Régulation de l’Expression Génétique, Institut Pasteur.
September 1995-November 1999:
Preparation of the PhD thesis delivered by Université de Versailles-Saint-Quentin-en-Yvelines, France. PhD director: Pr Alain Hénaut.
January 1995-June 1995:
Stay in the Unité de Régulation de l’Expression Génétique, Institut Pasteur: sequencing of the Bacillus subtilis genome.
1992-1994: Stay in the laboratory of Microbiology and Immunology at the Institute of Molecular Biology in Krakow, Poland: study of yeast artifical chromosomes (YACs).
November 1997:
Practical courses with 1st year students of Université de Versailles Saint-Quentin-en-Yvelines (cellular anatomy).
Students under my responsability
February 1999-March 1999:
Gillet J., stay for preparation of high level technician diploma "Construction of a transposon library " (sole supervisor)
March 1999-August 1999:
Seada P., stay for preparation of International Master of Science in Biotechnology diploma "Molecular genetics of polyamine biosynthesis in Bacillus subtilis 168" (sole supervisor).
September 2000-present:
Lu H. Y., preparation of the PhD thesis delivered by The University of Hong Kong.
A MEETING-PLACE FOR SULFUR AND NITROGEN METABOLISM:
POLYAMINE METABOLISM IN BACILLUS SUBTILIS
Deciphering the genome text of Bacillus subtilis uncovered a mine of unknown genes. My thesis work described polyamine metabolism in this bacterium. It further elaborates on its relationships with the still poorly known metabolism of sulfur. In B. subtilis arginine, decarboxylated by the product of the speA gene (wrongly assigned as cad, coding for a lysine decarboxylase) starts polyamine synthesis. An ureohydrolase, agmatinase, coded by the speB gene, subsequently produces putrescine. This molecule is the precursor of spermidine, synthesised by spermidine syntase (SpeE). speE and speB form an operon. We have extended our study to the phylogenetic analysis of ureohydrolases and spermidine synthases. This demonstrated that for polyamine metabolism Gram+ bacteria are quite close to archaebacteria, providing further insight into a heated controversy about the origins of the first cells. In addition our work showed, by combining in silico and in vivo / in vitro experiments, that many function assignments are erroneous in public databases. The pathway that leads to spermidine involves S-adenosylmethionine. We identified the corresponding decarboxylase (SpeD, a pyruvoyl-enzyme more similar to an orthologue that we have identified in Methanococcus jannaschii than to the enzyme in E. coli, an observation which again links Gram+ bacteria to archaebacteria), and discovered some enigmatic features of its expression. Finally, we analysed the fate of the accessory product of the reaction catalysed by SpeE, methylthioadenosine. Our study ended with a detailed analysis of the metabolism of this molecule, and more generally with the study of the metabolic cycles where the sulfur atom is involved. A general conclusion seems to emerge: many genes of unknown function are likely to be ordinary enzymes.
BIBLIOGRAPHY
1) Sekowska A. (1994) "The yeast artificial chromosome: structure and application". Proceedings of the Cell Biology Society Meetings 21(3):19-26 (in polish).
2) Presecan E., Moszer I., Boursier L., Cruz Ramos H., de la Fuente V., Hullo M.-F., Lelong C., Schleich S., Sekowska A., Song B. H., Villani G., Kunst F., Danchin A. & Glaser P. (1997) "The Bacillus subtilis genome from gerBC (311 degrees) to licR (334 degrees)". Microbiology 143 ( Pt 10):3313-28.
3) Kunst F., Ogasawara N., Moszer I., Albertini A. M., Alloni G., Azevedo V., Bertero M. G., Bessieres P., Bolotin A., Borchert S., Borriss R., Boursier L., Brans A., Braun M., Brignell S. C., Bron S., Brouillet S., Bruschi C. V., Caldwell B., Capuano V., Carter N. M., Choi S. K., Codani J. J., Connerton I. F., (…) Sekowska A., (…), Danchin A. (1997) "The complete genome sequence of the Gram-positive bacterium Bacillus subtilis". Nature 390:249-256.
4) Sekowska A., Bertin, P. & Danchin A. (1998) "Characterization of polyamine synthesis pathway in Bacillus subtilis 168". Molecular Microbiology 29:851-858.
5) Sekowska A. & Danchin, A. (1999) "A multipurpose technique for sequential gene replacement in Bacillus subtilis, identification of the yrrU gene as the methylthioadenosine nucleosidase gene". DNA Research 6:255-264.
6) Sabat A., Kosowska K., Poulsen K., Kasprowicz A., Sekowska A., van den Burg B., Travis J. & Potempa J. (2000) "Two allelic forms of the aureolysin gene aur within Staphylococcus aureus". Infection and Immunity 68:973-976.
7) Pedersen L.B., Ragkousi K., Cammett T.J., Melly E., Sekowska A., Schopick E., Murray T. & Setlow P. (2000) "Characterization of ywhE, which encodes a putative high-molecular-weight class A penicillin-binding protein in Bacillus subtilis." Gene 246:187-196.
8) Sekowska A., Kung H.-F. & Danchin A. (2000) "Sulfur metabolism in Escherichia coli and related bacteria: facts and fictions". Journal of Molecular Microbiology and Biotechnology 2:145-177.
9) Sekowska A., Coppée J.-Y., Le Caer J.-P., Martin-Verstraete I. & Danchin A. (2000) "S-adenoslymethionine decarboxylase of Bacillus subtilis is closely related to archaebactarial counterparts". Molecular Microbiology 36:1135-1147.
10) Sekowska A., Danchin A. & Risler J.-L. (2000) "Identification of related enzyme activities: the case of polyamine biosynthetic enzymes". Microbiology 146:1815-1828.
11) Rocha E., Sekowska A. & Danchin A. (2000) "Sulfur islands in the Escherichia coli genome: markers of the cell's architecture?". FEBS Letters 476:8-11.
12) Danchin A. & Sekowska A. (2000) "Expression profiling in reference bacteria: dreams and reality". Genome Biology 1 (4):1024.1-1024.5.
13) Rocha E., Moszer I., Klaerr-Blanchard M., Sekowska A., Médigue C., Viari A. & Danchin A. "In silico Genome Analysis", In "Functional Analysis of bacterial genomes: A Practical Manual" Wiley, New York (in press).
14) Hullo M.-F., Sekowska A., Presecan-Siedel E., Coppée J.-Y., Martin-Verstraete I., Glaser P. & Danchin A. "Screening for growth and lacZ reporter gene induction with metal ions and chelators, amino acids analogs, antibiotics, inhibitors of oxydative phosphorylation and miscellaneous stress factors", In "Functional Analysis of Bacterial Genes: A Practical Manual" Wiley, New York (in press).
15) Coppée J.-Y., Auger S. , Turlin E., Sekowska A., Le Caer J.-P., Labas V., Vagner V., Danchin A. & Martin-Verstraete I.
The sulphur limitation response in Bacillus subtilis
Microbiology (2001) 147: 000-000.
16) Sekowska A., Robin S., Daudin J.-J., Hénaut A. & Danchin A. (2001) "Extracting biological information from DNA arrays: an unexpected link between arginine and methionine metabolism in Bacillus subtilis". Genome Biology 2 (6):0019.1-0019.12.
17) Sekowska A., Mulard L., Krogh S., Tse J.K.S. & Danchin A. (2001) "MtnK, methylthioribose kinase, is a starvation-induced protein in Bacillus subtilis". BMC Microbiology 1:15.
18) Sekowska A., & Danchin A. (2001) "The methionine salvage pathway in Bacillus subtilis". BMC Microbiology 2 :8.
19) Kobayashi K., Ehrlich S.D., Albertini A., Amati G., Andersen K.K., Arnaud M., Asai K., Ashikaga S., Aymerich S., Bessieres P., Boland F., Brignell S. C., Bron S., Bunai K., Chapuis J., Christiansen L.C., Danchin A., Débarbouillé M., Dervyn E., Deuerling E., Devine K., Devine, S.K. , Dreesen, O., Errington J., Fillinger S. 8, Foster S.J., Fujita Y., Galizzi A., Gardan R., Eschevins C., Fukushima T., Haga K., Harwood C. R., Hecker M., Hosoya D., Hullo M.F., Kakeshita H., Karamata D., Kasahara Y., Kawamura F., Koga K., Koski, P., Kuwana R., Imamura D., Ishimaru M., Ishikawa S., Ishio I., Le Coq D., Mason A., Mauël C., Meima R., Mellado R.P., Moir A., Moriya S., Nagakawa E., Nanamiya H, Nakai S., Nygaard P., Ogura M., Ohanan T., O'Reilly, M., O'Rourke M., Pragai Z., Pooley H.M., Rapoport G., Rawlins, J.P., Rivas L.A., Rivolta C., Sadaie A., Sadaie Y., Sarvas M., Sato T., Saxild H.H., Scanlan E., Schumann W., Seegers J.F.M.L., Sekiguchi J., Sekowska A., Séror S., Simon M., Stragier P., Studer R., Takamatsu H., Tanaka T., Takeuchi M., Thomaides, H.B., Vagner V., van Dijl JM., Watabe K., Wipat A., Yamamoto H., Yamamoto M., Yamamoto Y., Yamane K., Yata K., Yoshida K., Yoshikawa H., Zuber U. and Ogasawara, N. (2003) "Essential Bacillus subtilis genes". Proceedings of the National Academy of Sciences of the United States of America 100 (8):4678-4683.
Patents
Sekowska A. & Danchin A. (2002) "The methionine salvage pathway in Bacillus". Docket n°222143US.
Seminars and Conferences
1994 Zakopane (Poland): Oral presentation during 23d Seminar of Institute of Molecular Biology in Krakow, Poland: “The yeast artificial chromosome”. Sekowska A.
1997 Newcastle (UK): Oral presentation during The Bacillus subtilis Functional Analysis workshop: "Progress report of participants from Institut Pasteur". Sekowska A. and Lelong C.
1997 Lausanne (Swizerland): Poster presentation during the 9th International Conference on Bacilli: "Functional analysis of the Bacillus subtilis genome. Exploration of intermediary metabolism". Sekowska A., Lelong C., Dreesen O., Nedjari H., Klaerr-Blanchard M., Moszer I., Glaser P. & Danchin A.
1999 Dourdan (France): Participation to the 6th European Meeting on Systematic analysis of Bacillus subtilis genes (Dourdan, 1-4.05.1999).
1999 Wroclaw (Poland): Participation to the XIII-th Maw Born Symposium (Wroclaw, 26-30.05.1999).
1999 Baveno (Italy): Participation to the 10th International Conference on Bacilli (Baveno, 27.06-1.07.1999).
2000 Paris (France): Poster presentation during the Genomes 2000 conference: "Global regulation of the sulfate strvation response in Bacillus subtilis". J.-Y. Coppée, S. Auger, E. Turlin, M.-F. Hullo, A. Sekowska, J.-P. Le Caer, V. Labas, A. Danchin & I. Martin-Verstraete.
2000 Hong Kong (China): Seminar at The University of Hong Kong, Department of Biochemistry, "Polyamine metabolism in Bacillus subtilis" A. Sekowska (Hong Kong 2.06.2000).2000 Oxford (UK): Participation to The Gordon Conference "Macromolecular organization and cell function" and poster presentation: "Global regulation of the sulfate starvation response in Bacillus subtilis". J.-Y. Coppée, S. Auger, E. Turlin, M.-F. Hullo, A. Sekowska, J.-P. Le Caer, V. Labas, A. Danchin & I. Martin-Verstraete.
2000 Paris Ffrance): Participation to the Transcriptome 2000 conference (Paris, 6-9.10.2000.
2000 Gif-sur-Yvette (France): Participation to the workshop Analyse statistique des données díexpression. Presentation "La préparation des sondes et des cDNA" A. Sekowska (Gif-sur-Yvette, 7-8.12.2000).
2000 Shanghai: Participation to Seminar on Bioinformatics & Microbial Genome Sequencing. Oral presentation "Polyamine metabolism in Bacillus subtilis (a model for genome annotation)" A. Sekowska (Shanghai, 19.12.2000).
2000 Peking (China): Invitation for a seminar at Beijing University "Polyamine metabolism in Bacillus subtilis (a model for genome annotation)" A. Sekowska (Pekin, 21.12.2000).
2001 Tokyo (Japan): Participation to International Symposium: Functional Genomics of Bacillus subtilis (Rikkyo University, Tokyo, 26-27.01.2001).
2001 Paris: Participation to BACELL 2001 (Paris, 9-12.04.2001).
2002 Pekin: Invitation for a seminar in Beijing University by Prof Wang Yiping (Dept. of Microbiology) "The methionine salvage pathway in Bacillus subtilis" A. Sekowska (Pekin, 27.06.2002).
2002 Paris: Invitation for a seminar in Institut de Biologie Physico-Chimique by Dr Harald Putzer " Le recyclage de la méthionine chez Bacillus subtilis " A. Sekowska (Paris, 15.07.2002).
2002 Chaville: Poster presentation at XIXe Journées françaises de Spectrométrie de Masse: "Analyse proteomique comparative chez Bacillus subtilis par gels 2D, MALDI-TOF MS et LC-MSMS : exploitation des résultats et étude de l'étalonnage interne en LC-MSMS". V. Labas, J. Vinh, E. Turlin, A. Sekowska (Chaville, 17-20.09.2002).
2002 Paris: Invitation for a seminar in Institut Pasteur by Pr Antoine Danchin "Gènes inconnus et cycles métaboliques. Le cycle de la récupération de la méthionine chez Bacillus subtilis et quelques autres" A. Sekowska (Paris, 12.12.2002).
