Interplanetary survival probability of Aspergillus terreus spores under simulated solar vacuum ultraviolet irradiation

δείτε την πρωτότυπη σελίδα τεκμηρίου
στον ιστότοπο του αποθετηρίου του φορέα για περισσότερες πληροφορίες και για να δείτε όλα τα ψηφιακά αρχεία του τεκμηρίου*



Interplanetary survival probability of Aspergillus terreus spores under simulated solar vacuum ultraviolet irradiation

Κεφαλάς, Αλκιβιάδης Κωνσταντίνος
Σαραντοπούλου, Ευαγγελία
Κόλλια, Ζωή
Gomoiu, I.

Άρθρο σε επιστημονικό περιοδικό

2011-01


Oxford
This work is a part of ESA/EU SURE project aiming to quantify the survival probability of fungal spores in space under solar irradiation in the vacuum ultraviolet (VUV) (110-180 nm) spectral region. The contribution and impact of VUV photons, vacuum, low temperature and their synergies on the survival probability of Aspergillus terreus spores is measured at simulated space conditions on Earth. To simulate the solar VUV irradiation, the spores are irradiated with a continuous discharge VUV hydrogen photon source and a molecular fluorine laser, at low and high photon intensities at 10(15) photon m(-2) s(-1) and 3.9 x 10(27) photons pulse(-1) m(-2) s(-1), respectively. The survival probability of spores is independent from the intensity and the fluence of photons, within certain limits, in agreement with previous studies. The spores are shielded from a thin carbon layer, which is formed quickly on the external surface of the proteinaceous membrane at higher photon intensities at the start of the VUV irradiation. Extrapolating the results in space conditions, for an interplanetary direct transfer orbit from Mars to Earth, the spores will be irradiated with 3.3 x 10(21) solar VUV photons m(-2). This photon fluence is equivalent to the irradiation of spores on Earth with 54 laser pulses with an experimental similar to 92% survival probability, disregarding the contribution of space vacuum and low temperature, or to continuous solar VUV irradiation for 38 days in space near the Earth with an extrapolated similar to 61% survival probability. The experimental results indicate that the damage of spores is mainly from the dehydration stress in vacuum. The high survival probability after 4 days in vacuum (similar to 34%) is due to the exudation of proteins on the external membrane, thus preventing further dehydration of spores. In addition, the survival probability is increasing to similar to 54% at 10 K with 0.12 K/s cooling and heating rates.

Αστρονομία (EL)
Astronomy (EN)

Aspergillus
VUV solar irradiation
Life and interplanetary travel
Panspermia

Αγγλική γλώσσα

Pergamon-elsevier Science Limited


Planetary and Space Science

https://rightsstatements.org/page/InC/1.0/?language=en
© 2010 Elsevier Ltd. All rights reserved.
© 2010 Elsevier Ltd. All rights reserved. (EN)




*Η εύρυθμη και αδιάλειπτη λειτουργία των διαδικτυακών διευθύνσεων των συλλογών (ψηφιακό αρχείο, καρτέλα τεκμηρίου στο αποθετήριο) είναι αποκλειστική ευθύνη των αντίστοιχων Φορέων περιεχομένου.