Michael Wasielewski’s pioneering work on the measurement of Photosystem II primary photochemistry has an important place in the history of photosynthesis, and we are proud to have been associated with him in those first measurements. Both Rienk Van Grondelle and Alfred Holzwarth have communicated to us their best wishes to MW on the occasion of his 60th birthday. Rienk writes: Mike is “a great guy and a great scientist”. Unfortunately, neither Alfred nor Rienk could attend the celebration. Acknowledgments We thank

Alfred Holzwarth, Rienk Van Grondelle, and Ryszard Jankowiak for reading this manuscript and making valuable suggestions to improve it. We are indebted to the Wazapalooza team (Sarah Mickley, Vickie Gunderson, Annie Butler Rick, and Dick Co, MW’s current graduate students, and postdocs who planned and executed the 60th birthday event at Northwestern University) for including us in this Great learn more Event. References Durrant JR, Hastings G, Joseph DM, Barber J, Porter G, Klug DR (1992) Subpicosecond equilibration of excitation energy in isolated Photosystem II reaction centers. Proc Natl Acad Sci USA 89:11632–11636 Fenton JM, Pellin MJ, Kaufmann K, Govindjee (1979) Primary photochemistry of the reaction center of Photosystem I. FEBS Lett 100:1–4CrossRefPubMed Govindjee, Wasielewski MR (1989) Photosystem II: from a femtosecond to a millisecond. In:

Briggs GE (ed) Photosynthesis. Alan Liss Publishers, NY, pp 71–103 MAPK inhibitor Greenfield SR, Wasielewski Selleck Crenigacestat M, Seibert M, Govindjee (1995) Femtosecond spectroscopy of PSII reaction centers: new results. In: Mathis P (ed) Photosynthesis: from light to biosphere, vol I. Kluwer Academic Publishers, Dordrecht, pp 663–666 Greenfield SR, Seibert M, Govindjee, Wasielewski MR (1996) Wavelength and intensity dependent primary photochemistry of isolated Photosystem II reaction centers at 5 C. Chem Phys 210:279–295CrossRef Greenfield SR, Seibert

M, Govindjee, Wasielewski MR (1997) Direct measurement of the effective rate constant for primary charge separation in isolated Photosystem II reaction centers. J Phys Chem B 101:2251–2255CrossRef Greenfield SR, Seibert M, Wasielewski MR (1999a) Time-resolved absorption changes of the pheophytin QX band in isolated Photosystem II reaction centers at 7 K: energy transfer and charge separation. J Phys Chem B 103:8364–8374CrossRef Greenfield SR, Wasielewski MR, Seibert M (1999b) Femtosecond PSII reaction center studies at 77 K. In: Garab G (ed) Photosynthesis: mechanisms, effects, vol II. Kluwer Academic Publishers, Dordrecht, pp 1029–1032 Groot ML, Pawlowicz NP, Van Wilderen LJGW, Breton J, Van Stokkum IHM, Van Grondelle R (2005) Initial electron donor and acceptor in isolated Photosystem II reaction center identified with femtosecond mid-IR spectroscopy.