title: Effect of long- and short-term exposure to laser light at 1070 nm on growth of Saccharomyces cerevisiae.
abstract: The effect of a 1070-nm continuous and pulsed wave ytterbium fiber laser on the growth of Saccharomyces cerevisiae single cells is investigated over a time span of 4 to 5 h. The cells are subjected to optical traps consisting of two counterpropagating plane wave beams with a uniform flux along the x, y axis. Even at the lowest continuous power investigated-i.e., 0.7 mW-the growth of S. cerevisiae cell clusters is markedly inhibited. The minimum power required to successfully trap single S. cerevisiae cells in three dimensions is estimated to be 3.5 mW. No threshold power for the photodamage, but instead a continuous response to the increased accumulated dose is found in the regime investigated from 0.7 to 2.6 mW. Furthermore, by keeping the delivered dose constant and varying the exposure time and power-i.e. pulsing-we find that the growth of S. cerevisiae cells is increasingly inhibited with increasing power. These results indicate that growth of S. cerevisiae is dependent on both the power as well as the accumulated dose at 1070 nm.
authors.affiliation: University of Copenhagen, Department of Food Science, Frederiksberg, Denmark. taa@life.ku.dk
authors.forename: Thomas
authors.initials: T
authors.lastname: Aabo
authors.forename: Ivan R
authors.initials: IR
authors.lastname: Perch-Nielsen
authors.forename: Jeppe Seidelin
authors.initials: JS
authors.lastname: Dam
authors.forename: Darwin Z
authors.initials: DZ
authors.lastname: Palima
authors.forename: Henrik
authors.initials: H
authors.lastname: Siegumfeldt
authors.forename: Jesper
authors.initials: J
authors.lastname: Glückstad
authors.forename: Nils
authors.initials: N
authors.lastname: Arneborg
mesh_terms: D049109:Cell Proliferation / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D008027:Light; D011829:Radiation Dosage; D012441:Saccharomyces cerevisiae / Q000502:physiology* / Q000528:radiation effects*