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96
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Introduction
Additional affiliations
March 2006 - August 2010
Jacobs Technology / NASA Johnson Space Center
Position
- Principal Investigator
October 2004 - April 2006
Position
- Senior Researcher
Description
- - Studied diversity and biogeochemical activity of siderophilic cyanobacteria - Isolated approximately 20 unialgal cultures of thermophilic cyanobacteria, provided polyphasic characterization of several strains.
December 2000 - October 2003
Position
- Research Associate
Description
- Taxonomy and biotechnology of thermophilic cyanobacteria
Publications
Publications (96)
Informal illustration to the article "The role of the sodium cycle of energy coupling in the emergence and persistence of natural foci of modern cholera"
Here, we report the draft genome sequence of the siderophilic cyano-bacterium Fischerella thermalis JSC-11, which was isolated from an iron-depositing hot spring. JSC-11 has bioremediation potential because it is capable of both extrac-ellular absorption and intracellular mineralization of colloidal iron. This genomic information will facilitate th...
The siderophilic, thermophilic Leptolyngbyaceae cyanobacterium JSC-12 was isolated from a microbial mat in an iron-depositing hot spring. Here, we report the high-quality draft genome sequence of JSC-12, which may help elucidate the mechanisms of resistance to extreme iron concentrations in siderophilic cyanobacte-ria and lead to new remediation bi...
The siderophilic, thermophilic Leptolyngbyaceae cyanobacterium JSC-12 was isolated from a microbial mat in an iron-depositing hot spring. Here, we report the high-quality draft genome sequence of JSC-12, which may help elucidate the mechanisms of resistance to extreme iron concentrations in siderophilic cyanobacteria and lead to new remediation bio...
Introduction: The success of selecting future Martian landing sites to discover extinct and/or extant extraterrestrial life is strongly dependent on the extent to which ancient and/or present habitable zones may have existed or presently exist on Mars. It has been suggested that early Mars could have been supportive for life since it was wet and wa...
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The Fischerella sp. JSC-11 whole genome shotgun (WGS) project has
the project accession NZ_AGIZ00000000. This version of the project
(01) has the accession number NZ_AGIZ01000000, and consists of
sequences AGIZ01000001-AGIZ01000034.
Despite the high potential for oxidative stress stimulated by reduced iron, contemporary iron-depositing hot springs with
circum-neutral pH are intensively populated with cyanobacteria. Therefore, studies of the physiology, diversity, and phylogeny
of cyanobacteria inhabiting iron-depositing hot springs may provide insights into the contribution of...
Background/Question/Methods
Precambrian phototrophic microbial mats were important drivers of Earth's biogeochemical cycles, but their impact on Archean atmospheric CO2 concentrations orders of magnitude larger than today is poorly understood. Modern microbial mats serve as models for interpreting Precambrian stromatolite fossils and for studying...
Introduction: Our ultimate goal in space is to be able to go anywhere, at any time with whatever capabilities to accomplish any task or job we choose to undertake. We are light-years away from achieving such a goal, largely because we must drag everything we need in space with us from the bottom of a very deep gravity well-the Earth's surface. As l...
Siderophilic (iron-loving) cyanobacteria were shown to use phosphates for sequestration of their internal Fe pool. The analysis of the genomes of siderophilic cyanobacteria indicates putative links between physical and molecular biosignatures.
Using genomic and metagenomic analysis, Fe-tolerant cyanobacterial species with a large and diverse set of stress-tolerant genes, were identified as prime candidates for in situ resource utilization in a biogeoreactor at extraterrestrial outposts.
Comparative analysis of the diversity of organisms in near neutral and acidified Fe-rich water bodies suggests that near neutral iron depositing hot springs have greater potential to preserve extinct or extant life on Mars.
The probability of Martian life (if it existed) on the eukaryotic level of the complexity is lower than on the prokaryotic level.
Conclusions Prokaryotes in iron-depositing hot spring may use different mechanisms to maintain Fe homeostasis and suppress oxidative stress than their counterparts in a fresh-water environment. In both springs, Bcp and Dps are concentrated within the cyanobacterial fractions of the microbial community (regardless of abundance). Dps in CP are not on...
Siderophilic (iron-loving) cyanobacteria were shown to use phosphates for sequestration of internal Fe pool. The analysis of the genomes of siderophilic cyanobacteria indicates putative links between physical and molecular biosignatures.
Goal: the reconstruction of ecophysiology of ancient cyanobacteria (CB). Objectives: study the mechanism(s) of the adaptation of iron-tolerant/ siderophilic CB to the fluctuations (up and down) of environmental [Fe]. Conclusions. The results suggest that colloidal Fe3+ is transported in the CB cytoplasm most likely through an ABC-type Fe3+ transpor...
The most critical conclusion is that a biological life support system tied to a geobioreactor might be more efficient for supporting an extraterrestrial outpost than a closed environmental system.
The study of mechanisms of the adaptation of iron-tolerant/siderophilic cyanobacteria to the excess and deficit of environmental iron
Oscillatoriales cyanobacterium JSC-1 16S ribosomal RNA gene,
partial sequence.
Perspectives: The most critical conclusion is that a semi-closed life support system tied to an ISRU biofacility might be more efficient for support of an extraterrestrial outpost than closed environmental systems. Such a synthesis of technological capability could decrease the demand for energy, transfer mass and cost of future exploration.
Perspectives: Preliminary results suggest that it would be reasonable to use the bioweathering poten-tial of litholytic CB for the transition of different chemical elements from extraterrestrial rocks to an aqueous phase where they will available for different applications, such as the preparation of substrates for hydroponic cultivation. The level...
The results on the bioweathering of lunar soil analogs by siderophilic CB are described in the abstract. Obtained results seem to be applicable to ISRU needs on the Moon.
Despite the harsh lunar environmental conditions, it seems possible to cultivate photosynthetic microorganisms using a closed bioreactor illuminated and heated by solar energy and to produce in-situ geochemical resources. Such bioprocessing might be simultaneously employed in critical ISRU and life support functions, e.g. air revitalization, propel...
Prior to 2.4 Ga, global oceans were likely significantly enriched in soluble iron (Rouxel, Bekker, Edwards, 2005), a condition that is not conducive to the growth of most contemporary mesophilic cyanobacteria (CB). Recent studies of the mechanisms of iron-deficiency stress in CB suggest that contemporary mesophilic freshwater and marine СB underwen...
Conclusion. CB species from iron depositing environment may provide therefore interesting models for the study Fe2+/Fe3+ transport through cytoplasmic membrane as well as for testing Y. Cohen hypothesis that PSI can directly oxidize Fe2+ (Cohen, 1989). Our results revealed significant variations in the physiological and bioenergetic responses of si...
Conclusion Despite the harsh lunar environmental conditions, it seems possible to cultivate photosynthetic microorganisms using a closed bioreactor illuminated and heated by solar energy. Such bioprocessing might be employed in critical ISRU functions; e.g., air revitalization, propellant (oxygen and methane) and food production, divalent cation ex...
The results on the bioweathering of analogs of lunar and martian soil analogs by siderophilic CB are described in the abstract. Obtained results seem to be applicable to ISRU needs on the Moon and Mars.
Introduction: A major goal for the Vision of Space Exploration is to extend human presence across the solar sys-tem. With current technology, however, all required consumables for these missions (propellant, air, food, water) as well as habitable volume and shielding to support human explorers will need to be brought from Earth. In-situ pro-duction...
General conclusion: Precambrian siderophilic cyanobacteria and their predecessors could have been involved not only in iron deposition but also in the global release of elements.
Proposal summary: To establish the experimental background for the development of both exploration and life support systems based on the bioconversion of extraterrestrial resources with the help of either cyanobacteria and/or their consortia. The main advantages of this proposed system are utilization of sunlight as energy and merging exploration f...
Iron oxide and hydroxide minerals, including hematite, can mineralize and preserve microfossils and physical biomarkers (Allen at al., 2004). Preserved remnants of phototrophic microorganisms are recognized as biosignatures of past life on Earth (Schopf, 2006). To date, two types of surface iron depositing environments have been studied as analogs...
MDA is designed as a test bed for an astrobiology field instrument to detect microbial metabolic activity in terrestrial or extraterrestrial geological soil samples. MDA employs electrochemical sensors in a unique differential chamber configuration, able to detect minute changes in the chemical composition between the two otherwise identical chambe...
We describe an instrument and methodology for definitive detection of microbial life via metabolic growth activity, with minimal assumptions using an array of metabolism-sensitive sensors and an advanced sample handling system.
We propose an alternative approach using iron-tolerant cyanobacteria. We have found that iron-tolerant cyanobacteria are capable of rapidly etching iron-bearing minerals. It may result in the breaking Fe-O bonds of common lunar iron oxide minerals including ilmenite, pseudobrookite, ferropseudobrookite, and armalcolite with the subsequent release o...
Iron is the fourth most abundant element in the Earth’s crust and the most abundant element in the Earth as a whole (Ehrilch,
2002). General agreement is that life evolved in the presence of soluble iron concentrations much greater than those typical
today (MacLeod et al., 1994; Emerson and Moyer, 2002) and that life is based, therefore, on redox p...
Background. Of all extant environs, iron-depositing hot springs (IDHS) may exhibit the greatest similarity to late Precambrian shallow warm oceans in regards to temperature, O2 gradients and dissolved iron and H2S concentrations. Despite the insights into the ecology, evolutionary biology, paleogeobiochemistry, and astrobiology examination of IDHS...
We propose an approach using iron-tolerant cyanobacteria. We have found that iron-tolerant cyanobacteria are capable of rapidly etching iron-bearing minerals. It may result in the breaking Fe-O bonds of common lunar iron oxide minerals including ilmenite, pseudobrookite, ferropseudobrookite, and armalcolite with the subsequent release of oxygen as...
Modern understanding of microbial ecology provides a lens through which
the accumulating knowledge of physiology, molecular phylogeny and
Earth's history can be integrated and focused on the phenomenon of
prokaryotic evolution.
The advanced goal of this project os to establish the experimental background for the development of both exploration and life support systems based on the bioconversion of extraterrestrial resources with teh help of either cyanobacteria and/or their consortia. The main advantages of this proposed system are that it might be energized by sun light...
Conclusion: There is no consensus on the divergence of cyanobacteria from a common ancestor for either anoxygenic or oxygenic phototrophs. Anoxygenic photosynthesis may have provided energy for the common ancestor, but it is unclear what environmental pressure induced the evolving of oxygenic phototrophs. It is supposed, however, that predecessors...
Conclusions Analysis of IT CB isolates and communities may be of value for frontier areas of exobiology and paleobiogeochemistry. In particular, they may provide insights into (1) the efficacy of iron oxides as a sunscreen for early photosynthetic microbes either on Earth or Mars (Bishop and Rothschild, 2004), (2) hematite deposition (Allen et al,...
Conclusion The division of marine cyanobacterium P. subcapitatum is accompanied with periodical deposition and dissolution of CaCO3 and both rhythms and intensity of those processes are dependent on concentrations of both OH- and Na+ in growth media. Thus, the role of marine cyanobacteria in global CaCO3 might be reduced to aggregation and re-cryst...
Studies directed at cyanobacteria inhabiting iron-depositing hot springs may provide insights into the role of both ancient and contemporary cyanobacteria mediated iron transformations. Here we phylogenetically, morphologically and physiologically characterize a novel cyanobacterium isolated from an iron-depositing hot spring. Phylogenetic analyses...
Extracellular accumulation of iron by iron-resistant CB may potentially serve three functions: to decrease the chemical potential of active (accessible for cells) iron [2], to produce a pool of reserve iron for times of low iron availability [3], and as protective sunscreen in hostile solar environments [4]. Iron/EPS casts are preserved after cell...
We are investigating biological mechanisms of terrestrial iron deposition as analogs for Martian hematite recently confirmed by. Possible terrestrial analogs include iron oxide hydrothermal deposits, rock varnish, iron-rich laterites, ferricrete soils, moki balls, and banded iron formations (BIFs). With the discovery of recent volcanic activity in...
Arthrospira (Spirulina) platensis (A. platensis) is a model organism for investigation of adaptation of photosynthetic organisms to extreme environmental conditions: the cell functions in this cyanobacterium are optimized to high pH and high concentration (150–250 mM) of Na+. However, the mechanism of the possible fine-tuning of the photosynthetic...
Surface translocation has been described in a large variety of microorganisms, including some gram-negative enteric bacteria.
Here, we describe the novel observation of the flagellum-independent migration of Vibrio cholerae and Escherichia coli on semisolid surfaces with remarkable speeds. Important aspects of this motility are the form of inoculat...
Wistar rats have been exposed to X-rays with a dose of 5 Gy. Significant decrease in dehydrogenase activity, energy-rich phosphate level and efficiency of antioxidant defence and significant increase in pyruvate amount were observed within 4 weeks. It was also found that the feeding of exposed rats with phycocyanin extract from blue-green algae Spi...
The hypothesis about the existence of Ca2+-driven bioenergetic cycle has been proposed. Recently it was found that some cyanobacterial species were able to grow in alkaline Ca2+ saturated media which restrict the generation of both H+ annd/or Na+ transmembrane electrochemical potentials. Ca2+ as well Na+ but not K+ was able to support light-induced...
A hypothesis on the appearance and persistence of natural foci of cholera based on ecological and bioenergetic features of the process has been developed. The main causes of persistence and propagation of modern cholera are: 1) inability of various bacteria, including the genus Vibrio and many cyanobacterial species, to perform energy coupling, dep...
The biogeochemical composition of water bodies existed on the Earth in early geological times, the role of electrochemical gradients in maintaining pH homeostasis, and the unusual ability of the cyanobacterium Gloeobacter violaceus to grow in Ca2+-rich alkaline media containing trace amounts of Na+ suggest that under conditions precluding delta myu...
Light-dependent Na+ and H+ transports, membrane potential (delta psi) and motility have been studied in the cells of the marine cyanobacterium Oscillatoria brevis. In the presence of a protonophorous uncoupler, carbonyl cyanide-m-chlorophenylhydrazone, the intracellular Na+ level is shown to increase in the dark and decrease in the light. The Na+/H...
The maximal growth rate of the marine cyanobacterium Oscillatoria brevis was reached at 200–400 mM NaCl and pH 9.0–9.6. NaCl was found (i) to stimulate the rate of the light-supported generation across the cytoplasmic membrane of the cells and (ii) to decrease the sensitivity of level and motility of the O. brevis trichomes to protonophorous uncoup...
The hypothesis that Na+ and K+ gradients have an energy storing function [V. P. Skulachev (1978) FEBS Lett. 87, 171–176] has been tested in experiments with Escherichia coli, the marine bacterium Vibrio harveyi, an extremely halophilic Halobacterium halobium and a fresh-water cyanobacterium Phormidium uncinatum from Lake Baikal living at an exterme...
The role of Na+/K+ gradients as a stabilizing factor for the energetics of bacterial cell has been evaluated. It was shown that in the presence of a Na+/K+ gradient across the membrane the cells of the unc mutant of E. coli retain their motility for some time under anaerobic conditions. This time coincides with that of dissipation of the K+ gradien...
The European Micro-Ecological Life Support System Alternative (MELiSSA) is an advanced idea for organizing a bioregenerative system for long term space flights and extraterrestrial settlements (Hendrickx, De Wever et al., 2005). Despite the hostility of both lunar and Martian environments to unprotected life, it seems possible to cultivate photosyn...
Questions
Questions (22)
Dear colleagues, especially from India -
Could you please share PDF file of this article: KOMAREKJ,. (1972). Reproduction process and
taxonomy of unicellular endosporine blue-green
algae. In Proceedings of the Symposium on
Taxonomy and Biology of Blue-Green Algae,
pp. 41-47. Edited by T. V. Desikachary. Madras,
India: University of Madras.
I'll appreciate your help very much.
Sincerely, Igor Brown
Hi, Could somebody please explain to me why lunar "soil" simulants JSC-1 and JSC-1A contain about 3% of ferric oxide while real lunar regolith do not have any ferric iron? Thank you, Igor Brown, PhD
I would like to cite an article containing comprehensive description of chemical composition of the majority of lunar and Martian simulants in my new MS. Which article could I find such information in?
Thank you in advance.
Igor Brown
Greetings colleagues -
As can be seen from Table 3 (below) published in 10.1007/s10853-018-3101-y some simulants of lunar regolith do contain from 3.5 up to 12% of Fe2O3 while all lunar regolith are practically free of Fe2O3. What was a reason to ad Fe2O3 to the simulants of lunar regolith?
Thank you,
Igor Brown
From Schleppi et at al (2019) Manufacture of glass and mirrors from lunar regolith simulant
Table 3 Compositional information of utilised regolith simulants Oxide JSC-2A LHT-3M EAC-1 FJS-1 SiO2 47.50 46.70 43.70 49.14 Al2O3 15.00 24.40 12.60 16.23 Fe2O3 3.50 4.16 12.00 4.77 FeO 7.25 – – 8.30 MgO 9.00 7.90 11.90 3.84 CaO 10.50 13.60 10.80 9.13 Na2O 2.75 1.26 2.90 2.75 K2O 0.80 0.08 1.30 1.01 TiO2 1.50 0.41 2.40 1.91 MnO 0.18 0.07 0.20 0.19 P2O5 0.80 0.15 0.60 0.44 Total 98.78 98.73 98.40 97.71
Dear colleagues -
Could I be confident that adding 1% SDS (V/V) into TE buffer and boiling cultures in tubes for 10 minutes would kill any living cell?
Thank you,
Igor Brown
Greetings colleagues,
Which of these three words is best to name the process of physico-chemical attack of microbes on a rock surface: biodeterioration, bioweathering or bioerrosion?
Thank you in advance for your suggestions.
Igor Brown
Hi, Colleagues -
I am writing an article where I would like to cite this article:
Krumbein WE, Jens K. Biogenic rock varnishes of the negev desert (Israel) an ecological study of iron and manganese transformation by cyanobacteria and fungi. Oecologia. 1981 Aug;50(1):25-38. doi: 10.1007/BF00378791. PMID: 28310059.
Can anyone send me the PDF of this article if you have it on your records?
Thank you in advance.
Igor Brown
Dear colleagues,
I am currently comparing some genomic features in different representatives of Fischerella genus isolated from different eco-types. Unfortunately, neither PCC nor UTEX collection of algae provide the history of PCC 9339/UTEX1829. I just found that UTEX 1829 was deposited by Professor G.L. Tiwari from the University of Allahabad (India) around 1971 but I was unable to find any word about the place of UTEX 1829 isolation. This is why I urge kindly my dear colleagues, especially from the Allahabad University, to share with me any information regarding the history of Fischerella sp. PCC 9339/Fischerella musciola (UTEX1829).
I thank you all in advance.
Igor Brown, PhD
