Study of carbon compounds in Apollo 12 and 14 lunar samples

The gases released on DF dissolution of a variety of samples have been studied by gas chromatography and high resolution mass spectrometry. Results on Apollo 12 samples confirm previous observations that CH₄ and C₂H₆ are released as well as CD₄, C₂D₄, C₂D₆ and higher deuterated hydrocarbons. The yields correlate with the total carbon content of the samples and the CH₄ and C₂H₆ released may be regarded as indigenous while the deuterated products result from hydrolysis of carbide material. Dissolutions were also performed on five size fractions of sample 14240,5, ranging from >420 to <37 . The yields of CH₄, CD₄,²⁰Ne and³⁶Ar correlate with the surface area and therefore probably arise from solar wind implantation. Other deuterocarbons released include C₂D₄, C₂D₆, C₃D₆, C₃D₈ and C₄D₁₀. Preliminary pyrolysis results of these size differentiated samples confirmed the presence and surface correlation of the CH₄,²⁰Ne and³⁶Ar. Dissolution of the 14148, 14156 and 14149 trench samples showed that their carbon chemistry and solar wind exposure are very similar to that of the 14240 SESC and Apollo 11 and 12 fines of high carbon content. Other interesting components released from the soil samples by DF include D₂S, DCN and CS₂.This paper is an amplified version of the comments made by Dr Holland during the discussions at the meeting on Lunar Analysis: Significance for Exobiology, held at College Park, Maryland, October 26–28, 1971.     

Compounds of the organogenic elements in Apollo 11 and 12 lunar samples: A review

Investigations of low molecular weight compounds of the organogenic elements on lunar samples are reviewed. The three general techniques of vacuum pyrolysis, acid hydrolysis, and crushing have been employed by most investigators. Vacuum pyrolysis of lunar fines produce a variety of gaseous species which are either: (1) indigenous, (2) solar wind products and/or (3) chemical reaction products of mineral phases found in the lunar samples. Acid hydrolysis of lunar fines using deuteriumlabeled acids yields evidence for indigenous methane and ethane. Methane and ethane found in the lunar fines are largely derived from the solar wind with only trace amounts indigenous to the samples. Crushing experiments with lunar fines and breccias produce methane, ethane, hydrogen, nitrogen, hydrogen sulfide and the rare gases.     

Search for amino acids in Apollo returned lunar soil.

The lunar samples from Apollo flights 11 through 17 provided the students of chemical evolution with an opportunity of examining extraterrestrial materials for evidence of early prebiological chemistry in the solar system. Our search was directed to water-extractable compounds with emphasis on amino acids. Gas chromatography, ion-exchange chromatography and gas chromatography combined with mass spectrometry were used for the analysis. It is our conclusion that amino acids are not present in the lunar regolith above the background levels of our investigations.     

Research for amino acids in lunar samples

Water extracts of lunar fines were analyzed for amino acids by a gas-liquid chromatographic technique whereby amino acids were converted to the N-trifluoroacetyln-butyl, esters prior to analysis. The lunar material studied included both Apollo 14 (14240 SESC and 14298) and Apollo 12 (12023) samples. The water extract of the special Apollo 14 sample (14240 SESC) was analyzed both for free and bound amino acids (hydrolysis with 6 N hydrochloric acid). In both the hydrolyzed and unhydrolyzed extracts, the amino acids were not observed above background levels.The analysis of Apollo 12 and 14 samples (12023 14298) yielded similar results. Detection limits were established at 300 pg to 1 ng for different amino acids. A large chromatographic peak with a retention temperature of 126°C was observed on analysis of sample, (12023); it was identified as oxalic acid by GC-MS. The concentration of amino acids in the Apollo 14 SESC samples processed and analyzed in the joint experiments at Ames by GLC and IEC were found to be extremely low (glycine at 3 to 4 ng g^–1). As the quantities were so minute, these identifications could not be confirmed by GLC-MS and therefore should still be considered as tentative. Other studies included the analysis of performance standards at the 2 to 6 ng level of each of 17 amino acids, and the analysis of 5 ml of H₂O containing 2 ppb of each amino acid. Recovery of amino acids added to lunar fines were conducted at the 10, 50, and 70 ng level of each amino acid with 50 to 70 mg of lunar material. The recoveries varied from as high as 80% for some of the aliphatics to complete loss of the amino acids ornithine and lysine.Contributed from Missouri Agricultural Experiment Station Journal Series No. 6255. Approved by the Director. Supported in part by grants from the National Aeronautics and Space Administration (NGR 26-004-011) and the Experiment Station Chemical Laboratories.     

Distribution and isotopic abundance of biogenic elements in lunar samples

A review of the abundance of six biologically important elements (H, C, N, O. P and S) demonstrates that they are present in trace amounts only in lunar matter analysed to date. To the endogenous lunar content, elements are contributed by solar wind irradiation and meteorite impacts. However, it is not yet possible to determine the relative importance of the three sources. Enrichment of the heavy isotopes, C¹³, O¹⁸, S³⁴ suggest that these elements may be lost from the lunar surface by hydrogen stripping (from solar wind protons) as volatile gases. The general lack of water, suggests that organic synthesis could not easily be accomplished in lunar rocks. High energy irradiation of the lunar surface may result in rapid destruction of organic matter not protected by a silicate matrix. It is apparent from present data available, that the ambient lunar surface could not support metabolism of known microorganisms.Publication No. 997 Institute of Geophysics and Planetary Physics, University of California at Los Angeles, Los Angeles, California 90024.     

In situ synthesis during organic analysis of lunar samples

In the development and application of extremely sensitive analytical techniques the need for extreme cleanliness and avoidance of contamination has been generally recognized and complied with in the organic analysis of lunar samples. Much less attention has been paid to the possibility of inadvertent synthesis of certain organic molecules from indigenous smaller organic or even inorganic constituents of the lunar material. At the part-per-billion level of detectability reactions proceeding even at very low yield can lead to detectable products. A particular area of concern should be the amino acid analysis since those substances are known to be formed by condensation of ammonia, cyanide and carbonyl compounds, all potential products of lunar material upon treatment with aqueous media.     

Microbial contamination associated with the Apollo 6 spacecraft during final assembly and testing

The National Aeronautics and Space Administration (NASA) requires that microorganisms which could contaminate the surface of the moon as the result of lunar missions be enumerated and identified so that life forms in lunar materials returned to earth may be more easily recognized as being of native or terrestrial origin.Assessment of microbial contamination in the intramural environments used for the assembly and test of the manned lunar spacecraft (Apollo) was made using fallout strips and air samplers. Microbial contamination on the surfaces of Apollo Command and Lunar Modules was determined by use of the swab-rinse method.Preliminary results indicate that the levels of microbial contamination which accumulated on exposed stainless steel surfaces, as well as airborne microbial contamination in the high bay assembly areas, were similar to those encountered in the unmanned spacecraft assembly areas. However, higher levels of microbial contamination were detected on the Apollo spacecraft than on the unmanned lunar spacecraft.     

Sperm contamination in archived and contemporary herring samples

Studies using archived scales and otoliths to examine ancient fish populations have become increasingly common, despite many methodological challenges in ancient DNA research. Here, we describe a case of DNA contamination in both modern and historical samples of Pacific herring (Clupea pallasii), where the source of the contamination is likely from milt spillage during collection. We describe a series of experiments to remove contamination using pre-extraction wash treatments. Though contamination was easily removed from contemporary fin clippings, no method was successful at removing contamination from historical scales. We discuss the implications of our findings to the genetic analysis of archived samples.     

Assessment of enterovirus contamination in mussel samples from Morocco

Summary In Morocco, shellfish sanitary quality analysis does not currently include enteric virus detection. Enteroviruses are classically detected by cell culture, but molecular methods such as RT-PCR are now broadly used alone or associated to cell culture. RT-PCR has the advantage of requiring less time and budget than cell culture. Bivalve mussels, being filter-feeders tend to accumulate viruses in contaminated seawater. In order to assess mussel contamination by enteroviruses, we screened samples of two origins, an aquaculture system and an area where wild mussels grow. Domestic sewage samples from an outlet near the above wild mussels growing area were also analysed. Viruses were concentrated from mussel meat by direct glycine elution and PEG 8000 precipitation. Total RNA was then extracted from the PEG precipitate by the guanidine thiocyanate method and used in RT-PCR. Enterovirus genomes were detected in 10% of wild shellfish samples, whilst none was present in the aquaculture samples. Since organisms harvested in both growing areas are used for human consumption, the enterovirus contamination observed in this study may highlight a potential public health risk and illustrate the importance of including routine virological analysis of shellfish in Morocco.     

Search for biogenic structures and viable organisms in lunar samples: A review

A review of the work on searches for biogenic structures and viable life forms in Apollo 11 and 12 samples shows no evidence for biology in these samples. The total amount of samples examined and the negative results from the variety of systems conducive to growth and metabolic activity make it highly improbable that life will be found in surface samples yet to be tested.     

Bioluminescent bioreporter for assessment of arsenic contamination in water samples of India

In the present study the most efficient R-factor controlling the ars operon was selected after screening of 39 Escherichia coli isolates by minimum inhibitory concentration test (MIC) studies from water samples of different geographical locations of India. Among all, strain isolated from Hooghly River (West Bengal) was found to have maximum tolerance towards arsenic and was further used for the development of bioreporter bacteria. Cloning of the ars regulatory element along with operator-promotor and luxCDABE from Photobacteria into expression vector has been accomplished by following recombinant DNA protocols. The bioreporter sensor system developed in this study can measure the estimated range of 0.74–60 μg of As/L and is both specific and selective for sensing bioavailable As. The constructed bacterial biosensor was further used for the determination of arsenic ion concentration in different environmental samples of India.     

Fungal flora and aflatoxin contamination of feedstuff samples in Beida Governorate,Libya

Fungi of 19 genera, 30 species, and one variety were isolated from 25 samples of sheep-, cattle- and camel feedstuffs collected from different farms in the Beida Governorate, Libya.Aspergillus, Penicillium andFusarium were the most common genera in the three substrates tested. TLC was used to establish the identity of aflatoxins in the chloroform extract of all samples and the ability to produce aflatoxins byAspergillus flavus in a synthetic liquid medium. Twenty samples out of 25 tested were naturally contaminated and 21 isolates ofA. flavus out of 30 produced at least one of the following aflatoxins: B₁; B₁, G₁; and B₁, B₂, G₁, G₂. This is the first report about the natural occurrence of aflatoxins and aflatoxin-producers of the genusAspergillus in Libya.     

Multiple sources of contamination in samples from patients reported to have XMRV infection

Xenotropic murine leukemia virus (MLV)-related retrovirus (XMRV) was reported to be associated with prostate cancer by Urisman, et al. in 2006 and chronic fatigue syndrome (CFS) by Lombardi, et al. in 2009. To investigate this association, we independently evaluated plasma samples from 4 patients with CFS reported by Lombardi, et al. to have XMRV infection and from 5 healthy controls reported to be XMRV uninfected. We also analyzed viral sequences obtained from supernatants of cell cultures found to contain XMRV after coculture with 9 clinical samples from 8 patients. A qPCR assay capable of distinguishing XMRV from endogenous MLVs showed that the viral sequences detected in the CFS patient plasma behaved like endogenous MLVs and not XMRV. Single-genome sequences (N = 89) from CFS patient plasma were indistinguishable from endogenous MLVs found in the mouse genome that are distinct from XMRV. By contrast, XMRV sequences were detected by qPCR in 2 of the 5 plasma samples from healthy controls (sequencing of the qPCR product confirmed XMRV not MLV). Single-genome sequences (N = 234) from the 9 culture supernatants reportedly positive for XMRV were indistinguishable from XMRV sequences obtained from 22Rv1 and XMRV-contaminated 293T cell-lines. These results indicate that MLV DNA detected in the plasma samples from CFS patients evaluated in this study was from contaminating mouse genomic DNA and that XMRV detected in plasma samples from healthy controls and in cultures of patient samples was due to cross-contamination with XMRV (virus or nucleic acid).     

Sensitivity of PCR assays for murine gammaretroviruses and mouse contamination in human blood samples

Gammaretroviruses related to murine leukemia virus (MLV) have variously been reported to be present or absent in blood from chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) patients and healthy controls. Using subjects from New York State, we have investigated by PCR methods whether MLV-related sequences can be identified in nucleic acids isolated from whole blood or from peripheral blood mononuclear cells (PBMCs) or following PBMC culture. We have also passaged the prostate cancer cell line LNCaP following incubation with plasma from patients and controls and assayed nucleic acids for viral sequences. We have used 15 sets of primers that can effectively amplify conserved regions of murine endogenous and exogenous retrovirus sequences. We demonstrate that our PCR assays for MLV-related gag sequences and for mouse DNA contamination are extremely sensitive. While we have identified MLV-like gag sequences following PCR on human DNA preparations, we are unable to conclude that these sequences originated in the blood samples.     

On the abiotic formation of amino acids I. HCN as a precursor of amino acids detected in extracts of lunar samples II. Formation of HCN and amino acids from simulated mixtures of gases released from lunar samples

Two studies on the abiotic formation of amino acids are presented. The first study demonstrates the role of hydrogen cyanide as a precursor of amino acids detected in extracts of lunar samples. The formation of several amino acids, including glycine, alanine, aspartic acid, and glutamic acid, under conditions similar to those used for the analysis of lunar samples is demonstrated. The second study investigates the formation of hydrogen cyanide as well as amino acids from lunar-sample gas mixtures under electrical discharge conditions. These results extend the possibility of synthesis of amino acids to planetary bodies with primordial atmospheres less reducing than a mixture of methane, ammonia, hydrogen and water.