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Wrenn, R. T.

Publications and source records attributed to Wrenn, R. T..

Postflight analyses of Bacillus thuringiensis organisms exposed to space flight conditions

Cultures of B. thuringiensis returned from space flight appeared to be normal to slightly affected adversely in their ability to produce three toxins that affect insects. In addition, it can be stated that B. thuringiensis spores are very resistant to ultraviolet irradiation at the individual wavelengths and energy levels previously described. Full sunlight, however, does have a detrimental effect on the viability of B. thuringiensis spores.

Wrenn, R. T.↗

Microbial response to space environment, part B

The performance of the microbial response to space environment experiment is considered excellent by all investigators. For most microbial systems, only preliminary survival data are available at this time. None of the available data indicate space flight-mediated changes in cell viability or recovery. One quite important observation has been made at this early date, however. The eggs produced after mice had been infected with N. dubius larvae demonstrated a significant decrease in hatchability when compared to identical ground controls. Except for the fact that the Apollo 16 flight larvae had been on board the command module, treatment of the flown larvae and ground control larvae was the same; neither had been exposed to UV irradiation. The significance and implications of this finding are currently being studied.

Taylor, G. R.↗