Protein Microarrays-Based Strategies for Life Detection in Astrobiology

Abstract

The detection of organic molecules of unambiguous biological origin is fundamental for the confirmation of present or past life. Planetary exploration requires the development of miniaturized apparatus for in situ life detection. Analytical techniques based on mass spectrometry have been traditionally used in space science. Following the Viking landers, gas chromatography-mass spectrometry (GC-MS) for organic detection has gained general acceptance and has been used successfully in the Cassini-Huygens mission to Titan. Microfluidics allows the development of miniaturized capillary electrophoresis devices for the detection of important molecules for life, like amino acids or nucleobases. Recently, a new approach is gaining acceptance in the space science community: the application of the well-known, highly specific, antibody-antigen affinity interaction for the detection and identification of organics and biochemical compounds. Antibodies can specifically bind a plethora of structurally different compounds of a broad range of molecular sizes, from amino acids level to whole cells. Antibody microarray technology allows us to look for the presence of thousands of different compounds in a single assay and in just one square centimeter. Herein, we discuss several important issues-most of which are common with other instruments dealing with life signature detection in the solar system-that must be addressed in order to use antibody microarrays for life detection and planetary exploration. These issues include (1) preservation of biomarkers, (2) the extraction techniques for biomarkers, (3) terrestrial analogues, (4) the antibody stability under space environments, (5) the selection of unequivocal biomarkers for the antibody production, or (6) the instrument design and implementation.

Microbial Biomarker Transition in High-Altitude Sinter Mounds From El Tatio (Chile) Through Different Stages of Hydrothermal Activity

“…The LDChip200 is a shotgun antibody microarray immunosensor produced to increase the success of detecting any microbial remain in natural samples, either for environmental monitoring and/or for detecting signs of life in planetary exploration (Rivas et al, 2008; Parro et al, 2008b, 2011b, 2018). Limitations related to the presence of relatively complex molecules from abiotic origin in other planetary bodies, are being presently achieved by adding new antibodies for detecting molecules such as aromatic amino acids or polyaromatic hydrocarbons (Moreno-Paz et al, 2018).…”

Detection of Macromolecules in Desert Cyanobacteria Mixed with a Lunar Mineral Analogue After Space Simulations

“…Technologies currently used for detecting traces of life on Mars, such as the one onboard NASA’s Mars Science Laboratory (Mahaffy et al 2012 ), are based on gas chromatography mass spectrometers. Other approaches include a miniaturized Raman spectrometer, planned as part of the Pasteur payload in the ESA-Roscosmos ExoMars mission (Barnes et al 2006 ; Vago et al 2006 ), antibody microarray devices such as the Signs of Life Detector instrument (Parro et al 2008 , 2011 ) proposed for the IceBreaker mission (McKay et al 2013 ), the Life Marker Chip (Sims et al 2012 ) planned for the ExoMars mission, Polymerase Chain Reaction (PCR)-based methods for targeting ribosomal RNA genes and DNA sequencing (Isenbarger et al 2008 ; Carr et al 2013 ). Complementary technologies based on laser induction of biomolecule autofluorescence were proposed to survey potential target regions before further analysis (Dartnell and Patel 2013 ).…”

The HADES mission concept – astrobiological survey of Jupiter's icy moon Europa

“…Complementary to the GC-MS analysis, the antibodies can cover a broad range of complex organic structures and extend the sensitivity of detection down to part-per-billion (ppb) levels (Fernandez-Calvo et al 2006 ;Parro et al 2007). The proposed HADES system is based on the SOLID 2 system, a multi-array competitive immunoassay currently under final development by the Centro de Astrobiologia INTA-CSIC (Parro et al 2007), with target molecules comprising widespread biomarkers of extant life, prebiotic compounds and paleomolecular remnants of ancient life forms. Antibody species will be carefully selected to be focused on molecules that are considered to be of exobiological relevance (e.g.…”

“…Antibody arrays have been proven to provide a powerful and highly sensitive tool for biomarker detection on Earth and have been proposed in many studies for astrobiological exploration in the Solar System. Complementary to the GC-MS analysis, the antibodies can cover a broad range of complex organic structures and extend the sensitivity of detection down to part-per-billion (ppb) levels (Fernandez-Calvo et al 2006; Parro et al 2007). The proposed HADES system is based on the SOLID 2 system, a multi-array competitive immunoassay currently under final development by the Centro de Astrobiologia INTA-CSIC (Parro et al 2007), with target molecules comprising widespread biomarkers of extant life, prebiotic compounds and paleomolecular remnants of ancient life forms.…”