Sage Journals: Discover world-class research

Abstract

Modeling risks for the forward contamination of planetary surfaces from endemic bioburdens on landed spacecraft requires precise data on the biocidal effects of space factors on microbial survival. Numerous studies have been published over the preceding 60 years on the survival of diverse microorganisms exposed to solar heating, solar ultraviolet (UV) irradiation, vacuum, ionizing radiation, desiccation, and many other planetary surface conditions. These data were generated with diverse protocols that can impair the interpretations of the results due to dynamic experimental errors inherent in all lab protocols. The current study (1) presents data on how metal surfaces can affect spore adhesion, (2) proposes doping and extraction protocols that can achieve very high recovery rates (close to 100%) from aluminum coupons with four Bacillus spp., (3) establishes a timeline in which dried spores on aluminum coupons should be used to minimize aging effects of spore monolayers, (4) confirms that vacuum alone does not dislodge spores dried on aluminum coupons, and (5) establishes that multiple UV irradiation sources yield similar results if properly cross-calibrated. The protocols are given to advance discussions in the planetary protection community on how to standardize lab protocols to align results from diverse labs into a coherent interpretation of how space conditions will degrade microbial survival over time.

Get full access to this article

View all access options for this article.

References

Beaty

, Buxbaum

, Meyer

, et al. (2006) Findings of the Mars Special Regions Science Analysis Group. Astrobiology, 6:677–732.

Brown

, Betty

, Brockmann

, et al. (2007) Evaluation of rayon swab surface sample collection method for Bacillus spores from nonporous surfaces. J Appl Microbiol, 103:1074–1080.

Cerf

(1977) Tailing of survival curves of bacterial spores. J Appl Bacteriol, 42:1–19.

Cockell

, Bush

, Bryce

, et al. (2016) Habitability: a review. Astrobiology, 16:89–117.

Des Marais

, Nuth JA

III

, Allamandola

, et al. (2008) The NASA Astrobiology Roadmap. Astrobiology, 8:715–730.

Dillon

, Gavin

, Roark

, et al. (1973) Estimating the number of terrestrial organisms on the Moon. Space Life Sci, 4:180–199.

Edmonds

, Collet

, Valdes

, et al. (2009) Surface sampling of spores in dry-deposition aerosols. Appl Environ Microbiol, 75:39–44.

Estill

, Baron

, Beard

, et al. (2009) Recovery efficiency and limit of detection of aerosolized Bacillus anthracis Sterne from environmental surfaces samples. Appl Environ Microbiol, 75:4297–4306.

Frick

, Mogul

, Stabekis

, et al. (2014) Overview of current capabilities and research and technology developments for planetary protection. Adv Space Res, 54:221–240.

10.

Garvin

, Figueroa

, and Naderi

(2001) NASA's new Mars Exploration Program: the trajectory of knowledge. Astrobiology, 1:439–446.

11.

Grand

, Bellon-Fontaine

M-N

, Herry

J-M

, et al. (2011) Possible overestimation of surface disinfection efficiency by assessment methods based on liquid sampling procedures as demonstrated by in situ quantification of spore viability. Appl Environ Microbiol, 77:6208–6214.

12.

Horneck

, Moeller

, Cadet

, et al. (2012) Resistance of bacterial endospores to outer space for planetary protection purposes—experiment PROTECT of the EXPOSE-E mission. Astrobiology, 12:445–456.

13.

Horneck

, Walter

, Westall

, et al. (2016) AstRoMap European Astrobiology Roadmap. Astrobiology, 16:201–207.

14.

Kminek

, Rummel

, Cockell

, et al. (2010) Report of the COSPAR Mars Special Regions colloquium. Adv Space Res, 46:811–829.

15.

La Duc

, Nicholson

, Kern

, et al. (2003) Microbial characterization of the Mars Odyssey spacecraft and its encapsulation facility. Environ Microbiol, 5:977–985.

16.

Levy

, Bornard

, and Carlin

(2011) Deposition of Bacillus subtilis spores using an airbrush-spray or spots to study surface decontamination by pulsed light. J Microbiol Methods, 84:223–227.

17.

Mancinelli

and Klovstad

(2000) Martian soil and UV radiation: microbial viability assessment on spacecraft surfaces. Planet Space Sci, 48:1093–1097.

18.

Moeller

, Setlow

, Horneck

, et al. (2008) Roles of the major, small, acid-soluble spore proteins and spore-specific and universal DNA repair mechanisms in resistance of Bacillus subtilis spores to ionizing radiation from X-rays and high-energy charged-particle bombardment. J Bacteriol, 190:1134–1140.

19.

Moeller

, Reitz

, Li

, et al. (2012) Multifactorial resistance of Bacillus subtilis spores to high-energy proton radiation: role of spore structural components and the homologous recombination and non-homologous end joining DNA repair pathways. Astrobiology, 12:1069–1077.

20.

Moores

and Schuerger

(2020) A cruise-phase microbial survival model for calculating bioburden reductions on past or future spacecraft throughout their missions with applications to Europa Clipper. Astrobiology, 20:1450–1464.

21.

Nicholson

(2003) Using thermal inactivation kinetics to calculate the probability of extreme spore longevity: implications for paleomicrobiology and lithopanspermia. Orig Life Evol Biosph, 33:621–631.

22.

Nicholson

and Galeano

(2003) UV resistance of Bacillus anthracis spores revisited: validation of Bacillus subtilis spores as UV surrogates for spores of B. anthracis Sterne. Appl Environ Microbiol, 69:1327–1330.

23.

Nicholson

, Munakata

, Horneck

, et al. (2000) Resistance of Bacillus endospores to extreme terrestrial and extraterrestrial environments. Microbiol Mol Biol Rev, 64:548–572.

24.

Noell

, Greenwood

, Lee

, et al. (2013) High-density, homogenous endospore monolayer deposition on test surfaces. J Microbiol Methods, 94:245–248.

25.

Panitz

, Horneck

, Rabbow

, et al. (2015) The SPORES experiment of the EXPOSE-R mission: Bacillus subtilis spores in artificial meteorites. Int J Astrobiol, 14:105–114.

26.

Probst

, Facius

, Wirth

, et al. (2010) Validation of a nylon-flocked-swab protocol for efficient recovery of bacterial spores from smooth and rough surfaces. Appl Environ Microbiol, 76:5148–5158.

27.

Probst

, Facius

, Wirth

, et al. (2011) Recovery of Bacillus spore contamination from rough surfaces: a challenge to space mission cleanliness control. Appl Environ Microbiol, 77:1628–1637.

28.

Raguse

, Fiebrandt

, Stapelmann

, et al. (2016) Improvement of biological indicators by uniformly distributing Bacillus subtilis spores in monolayers to evaluate enhanced spore decontamination technologies. Appl Environ Microbiol, 82:2031–2038.

29.

Rummel

, Beaty

, Jones

, et al. (2014) A new analysis of Mars “Special Regions”: Findings of the Second MEPAG Special Regions Science Analysis Group (SR-SAG2). Astrobiology, 14:887–968.

30.

Schubert

and Beaudet

(2011) Determination of lethality rate constants and D-values for heat-resistant Bacillus spores ATCC 29669 exposed to dry heat from 125°C to 200°C. Astrobiology, 11:213–223.

31.

Schuerger

, Mancinelli

, Kern

, et al. (2003) Survival of endospores of Bacillus subtilis on spacecraft surfaces under simulated martian environments: implications for the forward contamination of Mars. Icarus, 165:253–276.

32.

Schuerger

, Richards

, Hintze

, et al. (2005) Surface characteristics of spacecraft components affect the aggregation of microorganisms and may lead to different survival rates of bacteria on Mars landers. Astrobiology, 5:545–559.

33.

Schuerger

, Richards

, Newcombe

, et al. (2006) Rapid inactivation of seven Bacillus spp. under simulated Mars UV irradiation. Icarus , 181:52–62.

34.

Schuerger

, Farjardo-Cavazos

, Clausen

, et al. (2008) Slow degradation of ATP in simulated martian environments suggests long residence times for the biosignature molecule on spacecraft surfaces on Mars. Icarus, 194:86–100.

35.

Schuerger

, Moores

, Smith

, et al. (2019) A lunar microbial survival model for predicting the forward contamination of the Moon. Astrobiology, 19:730–756.

36.

Setlow

(2001) Resistance of spores of Bacillus species to ultraviolet light. Environ Mol Mutagenesis, 38:97–104.

37.

Shuster

, Khemmani

, Abe

, et al. (2019) Contributions of crust proteins to spore surface properties in Bacillus subtilis . Mol Microbiol, 111:825–843.

38.

Vaishampayan

, Rabbow

, Horneck

, et al. (2012) Survival of Bacillus pumilus spores for a prolonged period of time in real space conditions. Astrobiology, 12:487–497.

39.

Wassmann

, Moeller

, Rabbow

, et al. (2012) Survival of spores of the UV-resistant Bacillus subtilis strain MW01 after exposure to low-earth orbit and simulated Martian conditions: Data from the space experiment ADAPT on EXPOSE-E. Astrobiology, 12:498–507.

40.

Yunker

, Still

, Lohr

, et al. (2011) Suppression of the coffee-ring effect by shape-dependent capillary interactions. Nature, 476:308–311.

41.

Zhang

, Moeller

, Tran

, et al. (2018) Geobacillus and Bacillus spore inactivation by low energy electron beam technology: resistance and influencing factors. Front Microbiol, 9:1–10.

Supplementary Material

Please find the following supplemental material available below.

For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.

For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.

0.00 MB

0.02 MB

Microbial Protocols for Spacecraft: 1. Effects of Surface Texture,Low Pressure,and UV Irradiation on Recovery of Microorganisms from Surfaces

Abstract

Get full access to this article

References

Supplementary Material