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1.  Anaerobic utilization of phosphite and hypophosphite by Bacillus sp. 
A Bacillus sp. capable of utilizing phosphite and hypophosphite under anaerobic conditions was isolated from Cape Canerval soil samples. The organism was isolated on a glucose-mineral salts medium with phosphate deleted. Anaerobic cultivation of this isolate resulted in decreases in the hypophosphite or phosphite concentration, increases in turbidity, cell count, and dry-cell weight, and decreases in pH and glucose concentration. The optimum hypophosphite concentration for this isolate was 60 microgram/ml, whereas the optimum phosphate concentration was greater than 1,000 microgram/ml, suggesting that higher concentrations of hypophosphite may be toxic to this isolate. Hypophosphite or phosphite utilization was accompanied by little or no detectable accumulation of phosphate in the medium, and 32P-labeled hypophosphite was incorporated into the cell as organic phosphate. When phosphate was present in the medium, the isolate failed to metabolize phosphite. In the presence of phosphite and hypophosphite, the isolate first utilized phosphite and then hypophosphite.
PMCID: PMC242956  PMID: 26310
2.  Response of terrestrial microorganisms to a simulated Martian environment. 
Soil samples from Cape Canaveral were subjected to a simulated Martian environment and assayed periodically over 45 days to determine the effect of various environmental parameters on bacterial populations. The simulated environment was based on the most recent available data, prior to the Viking spacecraft, describing Martian conditions and consisted of a pressure of 7 millibars, an atmosphere of 99.9% CO2 and 0.1% O2, a freeze-thaw cycle of -65 degrees C for 16 h and 24 degrees C for 8 h, and variable moisture and nutrients. Reduced pressure had a significant effect, reducing growth under these conditions. Slight variations in gaseous composition of the simulated atmosphere had negligible effect on growth. The freeze-thaw cycle did not inhibit growth but did result in a slower rate of decline after growth had occurred. Dry samples exhibited no change during the 45-day experiment, indicating that the simulated Martian environment was not toxic to bacterial populations. Psychotrophic organisms responded more favorably to this environment than mesophiles, although both types exhibited increases of approximately 3 logs in 7 to 14 days when moisture and nutrients were available.
PMCID: PMC242914  PMID: 646358
3.  Evaluation of a new microquantity blood collector. 
Journal of Clinical Microbiology  1978;7(3):305-306.
A new device for collecting small amounts of blood from laboratory animals offer distinct advantages over standard syringes during the collection of serum or plasma.
PMCID: PMC274919  PMID: 649764
4.  Dry-heat resistance of selected psychrophiles. 
The dry-heat resistance characteristics of spores of psychrophilic organisms isolated from soil samples from the Viking spacecraft assembly areas at Cape Kennedy Space Flight Center, Cape Canaveral, Fla., were studied. Spore suspensions were produced, and dry-heat D values were determined for the microorganisms that demonstrated growth or survival under a simulated Martian environment. The dry-heat tests were carried out by using the planchet-boat-hot plate system at 110 and 125 degrees C with an ambient relative humidity of 50% at 22 degrees C. The spores evaluated had a relatively low resistance to dry heat. D(110 degrees C) values ranged from 7.5 to 122 min, whereas the D(123 degrees C) values ranged from less than 1.0 to 9.8 min.
PMCID: PMC242613  PMID: 410367

Results 1-4 (4)