Who Pro­duced The First Ul­tra­thin Sec­tion of Bac­te­ria?

Pic­tures Con­sid­ered #16

by Elio

It's hard to tell for sure, but it seems to have been a pair of in­ves­ti­ga­tors at the Uni­ver­sity of South­ern Cal­i­for­nia, Richard Baker and Daniel Pease, who pub­lished a pa­per in Na­ture in 1949 show­ing rather un­dif­fer­en­ti­ated sec­tions ofBacil­lus mega­terium that lack dis­cernible in­ter­nal de­tails. In­ter­est­ingly, the very next pa­per in that is­sue was by a Swedish investiga­tor, Helge Lau­rell, who used a strip­ping tech­nique in­stead of a mi­cro­tome to make sec­tions, with no bet­ter results.The first "mod­ern" ul­tra­thin sec­tion was pub­lished in 1953 by George Chap­man.

Orig­i­nal Leg­end : Trans­verse and lon­gi­tu­di­nal sec­tion of Bacil­lus megath­erium (as spelled then. Now it's me­ga­terium) ap­prox­i­mately 0.1 mi­cron thick. X 25,000; 50 KV. Note sim­i­lar den­sity and de­tail in the two cells.

It took many years to sort out the var­i­ous ar­ti­facts in­tro­duced in the meth­ods of fix­a­tion and pro­cess­ing used. At present, the gold stan­dard for elec­tron mi­cro­scopic stud­ies of bac­te­r­ial struc­ture is cryo-elec­tron to­mog­ra­phy.