•  Label free and label based proteomics
  
  
• Absolute protein quantification using targeted as well as global methods
  
  
• Post-translational modifications (especially phosphorylations and ubiquitinations)
  
  
•  Physiological responses of bacteria to infection-related stress conditions 

Alvarenga-Lucius, L, Linhartová, M, Schubert, H, Maaß, S, Becher, D, Hess, WR, Sobotka, R, and Hagemann, M(2023). The high-light-induced protein SliP4 binds to NDH1 and photosystems facilitating cyclic electron transport and state transition in Synechocystis sp. PCC 6803. New Phytol 239, 1083–1097. PMID: 37282607

Hüsler, D, Stauffer, P, Keller, B, Böck, D, Steiner, T, Ostrzinski, A, Vormittag, S, Striednig, B, Swart, Al, Letourneur, F, Maaß, S, Becher, D, Eisenreich, W, Pilhofer, M, and Hilbi, H(2023). The large GTPase Sey1/atlastin mediates lipid droplet- and FadL-dependent intracellular fatty acid metabolism of Legionella pneumophila. In: Zamboni, DS and Pfeffer, SR (eds.). eLife 12, e85142. PMID: 37158597

Öktem, A, Núñez-Nepomuceno, D, Ferrero-Bordera, B, Walgraeve, J, Seefried, M, Gesell Salazar, M, Steil, L, Michalik, S, Maaß, S, Becher, D, Mäder, U, Völker, U, and van Dijl, JM (2023). Enhancing bacterial fitness and recombinant enzyme yield by engineering the quality control protease HtrA of Bacillus subtilis. Microbiology Spectrum 0, e01778-23. PMID: 37819116

Schilling, T, Ferrero-Bordera, B, Neef, J, Maaβ, S, Becher, D, and van Dijl, JM (2023). Let there be light: Genome reduction enables Bacillus subtilis to produce disulfide-bonded Gaussia luciferase. ACS Synth Biol 12, 3656–3668. PMID: 38011677

Walgraeve, J, Ferrero-Bordera, B, Maaß, S, Becher, D, Schwerdtfeger, R, van Dijl, JM, and Seefried, M (2023). Diamide-based screening method for the isolation of improved oxidative stress tolerance phenotypes in Bacillus mutant libraries. Microbiology Spectrum 0, e01608-23. PMID: 37819171

Hadjeras, L, Bartel, J, Maier, L-K, Maaß, S, Vogel, V, Svensson, SL, Eggenhofer, F, Gelhausen, R, Müller, T, Alkhnbashi, OS, Backofen, R, Becher, D, Sharma, CM, and Marchfelder, A (2023). Revealing the small proteome of Haloferax volcanii by combining ribosome profiling and small-protein optimized mass spectrometry. microLife 4, uqad001. PMID: 37223747

Hadjeras, L, Heiniger, B, Maaß, S, Scheuer, R, Gelhausen, R, Azarderakhsh, S, Barth-Weber, S, Backofen, R, Becher, D, Ahrens, CH, Sharma CM, and Evguenieva-Hackenberg, E (2023). Unraveling the small proteome of the plant symbiont Sinorhizobium meliloti by ribosome profiling and proteogenomics. microLife 4, uqad012. PMID: 37223733

Matilla, MA, Genova, R, Martín-Mora, D, Maaβ, S, Becher, D and Krell, T (2023). The cellular abundance of chemoreceptors, chemosensory signaling proteins, sensor histidine kinases, and solute binding proteins of Pseudomonas aeruginosa provides insight into sensory preferences and signaling mechanisms. International Journal of Molecular Sciences 24, 1363. PMID: 36674894

Vormittag S, Hüsler D, Haneburger I, Kroniger T, Anand A, Prantl M, Barisch C, Maaß S, Becher D, Letourneur F, Hilbi H (2023). Legionella- and host-driven lipid flux at LCV-ER membrane contact sites promotes vacuole remodeling. EMBO Rep 2:e56007. PMID: 36588479.

Maaß S, Antelo-Varela M, Bonn F, Becher D (2023). Sample preparation for mass spectrometry-based absolute quantification of bacterial proteins in antibiotic stress research. Methods Mol Biol 2601:335-348. PMID: 36445593.

Raineri EJM, Maaß S, Wang M, Brushett S, Palma Medina LM, Sampol Escandell N, Altulea D, Raangs E, de Jong A, Vera Murguia E, Feil EJ, Friedrich,AW, Buist G, Becher D, García-Cobos S, Couto N, van Dijl, JM (2022). Staphylococcus aureus populations from the gut and the blood are not distinguished by virulence traits-a critical role of host barrier integrity. Microbiome 10(1):239. PMID: 36567349

Matilla MA, Udaondo Z, Maaß S, Becher D, Krell T (2022). Virulence induction in Pseudomonas aeruginosa under inorganic phosphate limitation: a proteomics perspective. Microbiol Spectr 10(6):e0259022. PMID: 36354317

Hochstrasser R, Michaelis S, Brülisauer S, Sura T, Fan M, Maaß S, Becher D, Hilbi H (2022). Migration of Acanthamoeba through Legionella biofilms is regulated by the bacterial Lqs-LvbR network, effector proteins and the flagellum. Environ Microbiol 24(8):3672-3692. PMID: 35415862

Song K, Hagemann M, Georg J, Maaß S, Becher D, Hess WR (2022). Expression of the cyanobacterial F₀F₁ ATP synthase regulator AtpΘ depends on small DNA-binding proteins and differential mRNA stability. Microbiol Spectr 29; 10(3):e0256221. PMID: 35446123

Sura T, Gering V, Cammann C, Hammerschmidt S, Maaß S, Seifert U, Becher, D (2022). Streptococcus pneumoniae and Influenza A Virus co-infection induces altered polyubiquitination in A549 cells. Front Cell Infect Microbiol 24(12):817532. PMID: 35281454.

Song K, Baumgartner D, Hagemann M, Muro-Pastor AM, Maaß S, Becher D, Hess WR (2022). AtpΘ is an inhibitor of F₀F₁ ATP synthase to arrest ATP hydrolysis during low-energy conditions in cyanobacteria. Curr Biol 32(1):136-148. PMID: 34762820.

Liao Y, Vogel V, Hauber S, Bartel J, Alkhnbashi OS, Maaß S, Schwarz TS, Backofen R, Becher D, Duggin IG, Marchfelder A. CdrS is a global transcriptional regulator influencing cell division in Haloferax volcanii. mBio. 2021 Jul 13:e0141621. PMID: 34253062.

Märkle P, Maier LK, Maaß S, Hirschfeld C, Bartel J, Becher D, Voß B, Marchfelder A. A small RNA is linking CRISPR-Cas and zinc transport. Front Mol Biosci. 2021 May 13. PMID: 34055875. 

Cassidy L, Kaulich PT, Maaß S, Bartel J, Becher D, Tholey A. Bottom-up and top-down proteomic approaches for the identification, characterization and quantification of the low molecular weight proteome with focus on short open reading frame-encoded peptides. Proteomics. 2021 Jun 19. PMID: 34145981.

Trautwein-Schult A, Bartel J, Maaß S, Becher D. Metabolic labeling of Clostridioides difficile proteins. Methods Mol Biol. 2021. PMID: 33950497.

Nepal S, Maaß S, Grasso S, Cavallo FM, Bartel J, Becher D, Bathoorn E, van Dijl JM. Proteomic charting of imipenem adaptive responses in a highly carbapenem resistant clinical Enterobacter roggenkampii isolate. Antibiotics (Basel). 2021 Apr 28. PMID: 33924830.

Maaß S, Bartel J, Mücke PA, Schlüter R, Sura T, Zaschke-Kriesche J, Smits SHJ, Becher D. Proteomic adaptation of Clostridioides difficile to treatment with the antimicrobial peptide nisin.Cells. 2021. https://www.mdpi.com/2073-4409/10/2/372.

Wencker FDR, Marincola G, Schoenfelder SMK, Maaß S,Becher D, Ziebuhr W. Another layer of complexity in Staphylococcus aureus methionine biosynthesis control: unusual RNase III-driven T-box riboswitch cleavage determines met operon mRNA stability and decay.  Nucleic Acids Res. 2021 Feb 26. PMID: 33450025.

Welle M, Pedersen JT, Ravnsborg T, Hayashi M, Maaß S, Becher D, Jensen ON, Stöhr C, Palmgren M. A conserved, buried cysteine near the P-site is accessible to cysteine modifications and increases ROS stability in the P-type plasma membrane H+-ATPase. Biochem J. 2021 Feb 12. PMID: 33427868.

Melior H, Li S, Stötzel M, Maaß S, Schütz R, Azarderakhsh S, Shevkoplias A, Barth-Weber S, Baumgardt K, Ziebuhr J, Förstner KU, Chervontseva Z, Becher D, Evguenieva-Hackenberg E. Reprograming of sRNA target specificity by the leader peptide peTrpL in response to antibiotic exposure. Nucleic Acids Res. 2021 Feb 22. PMID: 33619526.

Venturini, E, Svensson, SL, Maaß, S, Gelhausen, R, Eggenhofer, F, Li, L, et al. (2020). A global data-driven census of Salmonella small proteins and their potential functions in bacterial virulence. microLife 1. 

Mücke, P-A, Ostrzinski, A, Hammerschmidt, S, Maaß, S and Becher, D (2020). Proteomic adaptation of streptococcus pneumoniae to the antimicrobial peptide human beta defensin 3 (hbd3) in comparison to other cell surface stresses. Microorganisms 8, 1697. PMID: 33143252

Bartel, J, Varadarajan, AR, Sura, T, Ahrens, CH, Maaß, S and Becher, D (2020). Optimized proteomics workflow for the detection of small proteins. J. Proteome Res. 19, 4004–4018. PMID: 32812434

Voichek, M, Maaß, S, Kroniger, T, Becher, D and Sorek, R (2020). Peptide-based quorum sensing systems in Paenibacillus polymyxa. Life Science Alliance 3, e202000847. PMID: 32764104

Zhao, X, Chlebowicz-Flissikowska, MA, Wang, M, Vera Murguia, E, de Jong, A, Becher, D, et al. (2020). Exoproteomic profiling uncovers critical determinants for virulence of livestock-associated and human-originated Staphylococcus aureusST398 strains. Virulence 11, 947–963. PMID: 32726182

Lemay, M-L, Maaß, S, Otto, A, Hamel, J, Plante, P-L, Rousseau, GM, et al. (2020). A lactococcal phage protein promotes viral propagation and alters the host proteomic response during infection. Viruses 12, 797. PMID: 32722163

Melior, H, Maaß, S, Li, S, Förstner, KU, Azarderakhsh, S, Varadarajan, AR, et al. (2020). The leader peptide peTrpL forms antibiotic-containing ribonucleoprotein complexes for posttranscriptional regulation of multiresistance genes. mBio 11, e01027-20. PMID: 32546623

Antelo-Varela, M, Aguilar Suárez, R, Bartel, J, Bernal-Cabas, M, Stobernack, T, Sura, T, et al. (2020). Membrane modulation of super-secreting “midiBacillus” expressing the major Staphylococcus aureus antigen – a mass-spectrometry-based absolute quantification approach. Front. Bioeng. Biotechnol. 8. PMID: 32185169

Mücke, P-A, Maaß, S, Kohler, TP, Hammerschmidt, S and Becher, D (2020). Proteomic adaptation of Streptococcus pneumoniae to the human antimicrobial peptide LL-37. Microorganisms 8, 413. PMID: 32183275

Hentschker, C, Maaß, S, Junker, S, Hecker, M, Hammerschmidt, S, Otto, A, et al. (2020). Comprehensive spectral library from the pathogenic bacterium Streptococcus pneumoniae with focus on phosphoproteins. J. Proteome Res. 19, 1435–1446. PMID: 32154730

Hirschfeld, C, Gómez-Mejia, A, Bartel, J, Hentschker, C, Rohde, M, Maaß, S, et al. (2020). Proteomic investigation uncovers potential targets and target sites of pneumococcal serine-threonine kinase StkP and phosphatase PhpP. Front. Microbiol.10:3101. PMID: 32117081

Chi BK, Huyen NTT, Loi VV, Gruhlke MCH, Schaffer M, Mäder U, Maaß S, Becher D, Bernhardt J, Arbach M, Hamilton CJ, Slusarenka AJ, Antelmann H (2019). The disulfide stress response and protein S-thioallylation caused by allicin and diallyl polysulfanes in Bacillus subtilis as revealed by transcriptomics and proteomics. Antioxidants 8, 605. PMID: 31795512

Antelo-Varela M, Bartel J, Quesada-Ganuza A, Appel K, Bernal-Cabas M, Sura T, Otto A, Rasmussen M, van Dijl JM, Nielsen A, Maaß S, Becher D (2019). Ariadne’s thread in the analytical labyrinth of membrane proteins: integration of targeted and shotgun proteomics for global absolute quantification of membrane proteins. Anal. Chem. 91 (18), 11972-11980. PMID:31424929

Graf AC, Leonard A, Schäuble M, Rieckmann LM, Hoyer J, Maaß S, Lalk M, Becher D, Pané-Farré J, Riedel K (2019). Virulence factors produced by Staphylococcus aureus biofilms have a moonlighting function contributing to biofilm integrity. Mol. Cell Proteomics, 18 (6), 1036-1053. PMID: 30850421

Maaß S, Moog G, Becher, D (2019). Subcellular protein fractionation in Legionella pneumophila and preparation of the derived sub-proteomes for analysis by mass spectrometry. In: Buchrieser, C and Hilbi, H (eds.). Legionella: Methods and Protocols, Springer, New York, NY, pp 445–464. PMID:30694509

Lemay M-L, Otto A, Maaß S, Plate K, Becher D, Moineau, S (2019). Investigating Lactococcus lactis MG1363 response to phage p2 infection at the proteome level. Mol. Cell Proteomics, 18 (4), 704-714. PMID: 30679258

Maaß S, Otto A, Albrecht D, Riedel K, Trautwein-Schult A, Becher D. Proteomic signatures of Clostridium difficile stressed with metronidazole, vancomycin, or fidaxomicin. Cells. 2018. 7, 213. PMID:30445773

Trautwein-Schult A, Maaß S, Plate K, Otto A, Becher D. A metabolic labeling strategy for relative protein quantification in Clostridioides difficile. Front. Microbiol. 2018. 9. PMID: 30386308

Bonn F, Maaß S. van Dijl JM. Enrichment of cell surface-associated proteins in gram-positive bacteria by biotinylation or trypsin shaving for mass spectrometry analysis. Methods in Molecular Biology (Clifton, N.J.). 2018. 1841, pp 35–43. PMID:30259478

Junker S, Maaß S, Otto, A, Hecker M, Becher D. Toward the quantitative characterization of arginine phosphorylations in Staphylococcus aureus. J. Proteome Res. 2018. doi:10.1021/acs.jproteome.8b0057911. PMID:30358407

Maaß S. Absolute protein quantification using AQUA-calibrated 2D-PAGE. Methods in Molecular Biology (Clifton, N.J.). 2018. 1841, pp 141–16212. PMID:30259485

Otto A, Maaß S, Bonn F, Büttner K, Becher D. An easy and fast protocol for affinity bead-based protein enrichment and storage of proteome samples. In: Shukla, AK (ed.). Methods in Enzymology. 2017. 585, Academic Press, pp 1–13.

Hoyer J, Bartel J, Gómez-Mejia A, Rohde M, Hirschfeld C, Heß N, Sura T, Maaß S, Hammerschmidt S, Becher D. Proteomic response of Streptococcus pneumoniae to iron limitation. International Journal of Medical Microbiology. 2018. doi:10.1016/j.ijmm.2018.02.001. PMID:29496408

Junker S, Maaß S, Otto A, Michalik S, Morgenroth F, Gerth U, et al.. Spectral library based analysis of arginine phosphorylations in Staphylococcus aureus. Mol. Cell Proteomics. 2017.doi:10.1074/mcp.RA117.000378. PMID:29183913

Hillion M, Imber M, Pedre B, Bernhardt J, Saleh M, Loi VV, et al. The glyceraldehyde-3-phosphate dehydrogenase GapDH of Corynebacterium diphtheriae is redox-controlled by protein S -mycothiolation under oxidative stress. Scientific Reports. 2017. 7, 5020. PMID:28694441

Hillion M, Bernhardt J, Busche T, Rossius M, Maaß S, Becher D, et al. Monitoring global protein thiol-oxidation and protein S-mycothiolation in Mycobacterium smegmatis under hypochlorite stress. Sci Rep. 2017. 7, 1195. PMID:28446771

Bonn F, Maass S, Becher D. Sample preparation for mass-spectrometry based absolute protein quantification in antibiotic stress research. In: Sass, P (ed.). Antibiotics, 2017, Springer New York, pp 281–289. PMID:27873259

Otto A, Maaß S, Lassek C, Becher D, Hecker M, Riedel K, Sievers S. The protein inventory of Clostridium difficile grown in complex and minimal medium. Proteomics Clin Appl. 2016. 10(9-10):1068-1072. PMID:27511832

Zühlke D, Dörries K, Bernhardt J, Maaß S, Muntel J, Liebscher V, Pané-Farré J, Riedel K, Lalk M, Völker U, Engelmann S, Becher D, Fuchs S, Hecker M. Costs of life - Dynamics of the protein inventory of Staphylococcus aureus during anaerobiosis. Scientific Reports. 2016. 6:28172. PMID: 27344979

Maaß S, Becher D. Methods and applications of absolute protein quantification in microbial systems. J Proteomics. 2016. 136:222–233. PMID:26825536

Salzberg LI, Botella E, Hokamp K, Antelmann H, Maaß S, Becher D, Noone D, Devine KM. A genome-wide analysis of PhoP∼P binding to chromosomal DNA reveals several novel features of the PhoPR-mediated phosphate limitation response in Bacillus subtilis. J. Bacteriol. 2015. 197(8):1492-1506. PMID: 25666134

Kohlstedt M, Sappa PK, Maaß S, Zaprasis A, Hoffmann T, Becker J, Steil L, Hecker M, van Dijl JM, Lalk M, Mäder U, Stülke J, Bremer E, Völker U, Wittmann C. Adaptation of Bacillus subtilis carbon core metabolism to simultaneous nutrient limitation and osmotic challenge: a multi-omics perspective. Environ Microbiol. 2014. 16(6):1898-1917. PMID:24571712

Maaß S, Wachlin G, Bernhardt J, Eymann C, Fromion V, Riedel K, Becher, D, Hecker M. Highly precise quantification of protein molecules per cell during stress and starvation responses in Bacillus subtilis. Mol Cell Proteomics. 2014. 13:2260–2276. PMID: 24878497

Muntel J, Fromion V, Goelzer A, Maaβ S, Mäder U, Büttner K, Hecker M, Becher D. Comprehensive absolute quantification of the cytosolic proteome of Bacillus subtilis by data independent, parallel fragmentation in liquid chromatography/mass spectrometry (LC/MS^E). Mol. Cell Proteomics. 2014. 13:1008–1019. PMID: 24696501

Moche M, Albrecht D, Maaß S, Hecker M, Westermeier R, Büttner K. The new horizon in 2D electrophoresis -new technology to increase resolution and sensitivity. Electrophoresis. 2013. 34:1510–1518. PMID: 23494680

Maaß S, Sievers S, Zühlke D, Kuzinski J, Sappa PK, Muntel J, Hessling B, Bernhardt J, Sietmann R, Völker U, Hecker M, Becher D. Efficient, global-scale quantification of absolute protein amounts by integration of targeted mass spectrometry and two-dimensional gel-based proteomics. Analytical Chemistry. 2011. 83:2677–2684. PMID: 21395229

Tefon BE, Maaß S, Ozcengiz E, Becher D, Hecker M, Ozcengiz G. A comprehensive analysis of Bordetella pertussis surface proteome and identification of new immunogenic proteins. Vaccine. 2011. 29:3583–3595. PMID: 21397717