▁focused ▁on ▁the ▁role ▁of ▁o xygen ▁in ▁the ▁lum ines c ence ▁of ▁b acter ia , ▁fire f lies , ▁ost rac od ▁cr ust ace ans ▁and ▁fung i . ▁He ▁received ▁his ▁Ph D ▁in ▁ 1 9 5 1 . ▁He ▁then ▁joined ▁the ▁lab ▁of ▁William ▁D . ▁Mc El roy , ▁another ▁student ▁of ▁Har vey ’ s , ▁at ▁Joh ns ▁Hop kins ▁University ▁where ▁he ▁discovered ▁both ▁the ▁stim ul atory ▁effects ▁of ▁co enz yme ▁A ▁and ▁g ating ▁control ▁by ▁o xygen ▁of ▁fire fly ▁lum ines c ence , ▁and ▁that ▁fla vin ▁is ▁a ▁substr ate ▁in ▁b acter ial ▁lum ines c ence . ▁ ▁In ▁ 1 9 5 3 ▁he ▁joined ▁the ▁fac ulty ▁in ▁the ▁Department ▁of ▁Bi ological ▁Sciences ▁at ▁North western ▁University . ▁In ▁ 1 9 5 4 ▁he ▁began ▁a ▁long ▁collaboration ▁with ▁Be atrice ▁M . ▁S ween ey , ▁who ▁was ▁then ▁at ▁the ▁S cri pp s ▁Institution ▁of ▁Ocean ography , ▁in ▁el uc id ating ▁the ▁cell ular ▁and ▁bio chem ical ▁mechan isms ▁of ▁lum ines c ence ▁in ▁the ▁un ic ell ular ▁din of lag ell ate ▁L ing ul od in ium ▁poly ed rum ▁( former ly ▁known ▁as ▁G ony a ul ax ▁poly ed ra ). ▁A ▁by product ▁of ▁this ▁initial ▁research ▁was ▁their ▁discovery ▁of ▁circ ad ian ▁control ▁of ▁the ▁lum ines c ence . ▁ ▁In