CHEMOTAXIS AND ITS CORRELATION WITH PHOTO RESPONSE IN CHLAMYDOMONAS-REINHARDTII STRAIN WITH NEGATIVE PHOTOTAXIS

A positive chemotaxis to sugars (maltose, sucrose, and xylose) and man nite has been studied by the capillary method in a Chlamydomonas reinh ardtii strain 495 with negative phototaxis. Addition of an attractant to the suspension of mobile cells temporarily inhibited the photorespo nse at light intensity of 6 and 18 W/m(2), while at 90 W/m(2) no inhib itory effect of the attractant was observed. The phototaxis response w as completely restored after a period of time necessary for cell adapt ation to a chemical effector. Adaptation time was 15-20 min in our exp eriments. Glucose did not serve as an attractant for mobile Chlamydomo nas cells and did not affect their photoresponse. Chemotaxis was simil ar in the Chlamydomonas wild type strain and the mutant one with negat ive phototaxis.