MARSBUGS: The Electronic Astrobiology Newsletter Volume 5, Number 21, 18 September 1998. Editors: Dr. David Thomas, Department of Biological Sciences, University of Idaho, Moscow, ID, 83844-3051, USA. Marsbugs@aol.com or davidt@uidaho.edu. Dr. Julian Hiscox, Division of Molecular Biology, IAH Compton Laboratory, Berkshire, RG20 7NN, UK. Julian.Hiscox@bbsrc.ac.uk Marsbugs is published on a weekly to quarterly basis as warranted by the number of articles and announcements. Copyright of this compilation exists with the editors, except for specific articles, in which instance copyright exists with the author/authors. While we cannot copyright our mailing list, our readers would appreciate it if others would not send unsolicited e-mail using the Marsbugs mailing list. The editors do not condone "spamming" of our subscribers. Persons who have information that may be of interest to subscribers of Marsbugs should send that information to the editors. E-mail subscriptions are free, and may be obtained by contacting either of the editors. Article contributions are welcome, and should be submitted to either of the two editors. Contributions should include a short biographical statement about the author(s) along with the author(s)' correspondence address. Subscribers are advised to make appropriate inquiries before joining societies, ordering goods etc. Back issues and Word97 files suitable for printing may be obtained via anonymous FTP at ftp.uidaho.edu/pub/mmbb/marsbugs or at the official Marsbugs web page at http://members.aol.com/marsbugs/marsbugs.html. The purpose of this newsletter is to provide a channel of information for scientists, educators and other persons interested in exobiology and related fields. This newsletter is not intended to replace peer-reviewed journals, but to supplement them. We, the editors, envision Marsbugs as a medium in which people can informally present ideas for investigation, questions about exobiology, and announcements of upcoming events. Astrobiology is still a relatively young field, and new ideas may come out of the most unexpected places. Subjects may include, but are not limited to: exobiology and astrobiology (life on other planets), the search for extraterrestrial intelligence (SETI), ecopoeisis and terraformation, Earth from space, planetary biology, primordial evolution, space physiology, biological life support systems, and human habitation of space and other planets. ------------------------------------------------------------------ CONTENTS 1) JODRELL BANK SEARCHES FOR EXTRATERRESTRIAL CIVILIZATIONS University of Manchester press release PR9802 2) LAB RECEIVES NASA FUNDING TO TEST CRITICAL INSTRUMENT COMPONENTS FOR POSSIBLE USE ON FUTURE EUROPA MISSION Los Alamos National Laboratory release 3) FOSSILIZED MAGNETOTACTIC BACTERIUM IN THE ORGUEIL METEORITE By Brig Klyce 4) GREAT BUGS OF FIRE: PROTEIN FROM VOLCANO-LOVING BUG CRYSTALLIZED IN SPACE By David Noever 5) NATURE'S "ELECTRONIC INK": RETINAL PROTEIN CRYSTALLIZED ON SPACE MISSION By David Noever 6) NATURE'S SUGAR HIGH: SPACELAB SUCCESSFULLY CRYSTALLIZES INTENSELY SWEET PROTEIN By David Noever ------------------------------------------------------------------ JODRELL BANK SEARCHES FOR EXTRATERRESTRIAL CIVILIZATIONS University of Manchester press release PR9802 12 September 1998 The University of Manchester's Lovell radio telescope at Jodrell Bank has begun to take part in the most sensitive and comprehensive search ever undertaken for radio communications signals from Extra-Terrestrial Civilizations beyond our Solar System. The collaborative research program with the SETI Institute, called Project Phoenix, is using the 76-m Lovell telescope and the 305-m Arecibo telescope, located in Puerto Rico. The radio telescopes have begun to make observations of the regions around several hundred Sun-like stars that lie within a distance of 200 light years. Ian Morison, who is coordinating the Jodrell Bank observations, explained that, "Astronomers expect that other civilizations are most likely to be found on planets in orbit around stars similar to our Sun. Such stars live long enough and provide enough heat to allow life a chance to evolve." Jodrell Bank is a world leader in the development of advanced radio receivers which when used with the Lovell telescope, the second largest fully-steerable radio telescope in the world, make it exceptionally sensitive to faint radio signals. Jill Tarter, Director of the SETI Institute, points out that "by using the Arecibo and Lovell telescopes in the search we will have the most sensitive system possible." The privately-funded SETI Institute, in California, has continued the development of a NASA multi-million-channel receiver, which is capable of efficiently searching a wide band of frequencies where extra-terrestrial signals might be found. The receiver is located at the Arecibo telescope and will be used to make the initial detection of signals having the appropriate characteristics. The Lovell telescope will then be immediately used to eliminate earth- based interference or confirm any suspected extra-terrestrial signal. Previous searches for Life in the Universe have always been plagued with the problem of discriminating between a "true" extra-terrestrial signal and those originating on Earth or from artificial satellites. As Ian Morison explains: "local signals are eliminated by making simultaneous observations with the two radio telescopes. Due to their transatlantic separation, a signal has to come from a very great distance, from at least the outer part of our solar system, for the computer-based detection systems to be triggered at both telescopes. Fortunately, we can make a regular check on the system by receiving the signal from the Pioneer 10 spacecraft, now far beyond the orbit of Pluto." The search is being undertaken during two three-week observing sessions each year and will continue for several years. As Professor Andrew Lyne, Director of Jodrell Bank, said "If an extra-terrestrial signal were detected, it would be one of the most dramatic discoveries ever made. We are glad that we can make a contribution to this exciting scientific quest." The support material at http://www.jb.man.ac.uk/research/seti gives background to: 1. The history of SETI and The SETI Institute. 2. Project Phoenix--of which these observations are a part. 3. SETI Questions--Answers to often asked questions given by Jill Tarter and Ian Morison. 4. The Drake Equation--a look at the probability of contacting other civilizations. ------------------------------------------------------------------ LAB RECEIVES NASA FUNDING TO TEST CRITICAL INSTRUMENT COMPONENTS FOR POSSIBLE USE ON FUTURE EUROPA MISSION Los Alamos National Laboratory release 16 September 1998 Los Alamos National Laboratory scientists recently received a $120,000 grant from NASA to use Laboratory space instrument design and manufacturing expertise and test critical components of an instrument that may lead to a final product for use on a future mission to the Jupiter moon Europa. Concurrently, three Los Alamos researchers are part of a 17-member international team working on a feasibility study for NASA to determine the technical requirements for an instrument to study the moon's icy surface. The preliminary report is due November 1. Called the Ice Penetrating Radar, the instrument would use a three-antenna array that sends millions of radar signals at different frequencies to map out the thickness of Europa's ice surface and detect, if present, a subsurface Europan ocean. The IPR also would characterize Europa's ice surface. A liquid ocean is the most important ingredient in the development and sustenance of life; detecting and characterizing Europa's oceans, if present, are an integral part of scientists' search for evidence of life in the solar system. "If we can confirm the existence of a water ocean on Europa, it would be the only ocean known to exist in our solar system outside of Earth's," said Brad Edwards of Los Alamos' Space and Remote Sensing Sciences Group. Edwards also is part of the 17-member Instrument Definition Team, which includes researchers from around the world. Because ice is transparent to a large range of radar signals, the IPR will be able to record waves reflected off the top layer of ice and the ice-water interface, ultimately converting them into three-dimensional images. "We think the ice crust surface could be as deep as 100 kilometers, but data we received from the Galileo spacecraft indicate that the ice could be as thin as hundreds of meters," explained Edwards. Photos transmitted by the Galileo spacecraft in 1994 presented the first evidence of the possible existence of liquid water on Europa. "If a water ocean does exist on Europa, the IPR can map thin areas of the ice surface for future lander missions to Europa to sample the water for signs of life," said Edwards. Edwards said the Instrument Definition Team currently is studying many things, including how to distinguish the different radar reflection signals returned by rocks, cracks in the ice, salty and non-salty ice, and other conditions on the moon's surface. Another obstacle is making sure the IPR survives Jupiter's intense radiation that surrounds Europa, he added. "The radiation around Europa measures about 25 megarads per month. That's enough radiation to fry a desktop computer in about five minutes," he said. Still another important consideration is determining just how much power the IPR will need in order to transmit and receive its radar signals and the kinds of antennas that need to be used, said Xuan- Min Shao of Los Alamos' Space and Atmospheric Sciences Group and fellow IDT member. Shao said he hopes to begin testing the IPR prototype's antennas within the next couple of months. The testing will take place at Los Alamos. Shao said the instrument's weight is another major factor in designing and building the prototype. "We think the Ice Penetrating Radar should weigh no more than eight kilograms," he said, or about 17 pounds. The final draft design for the IPR is scheduled to be submitted to NASA sometime in March 1999, said Edwards. At that time, NASA will put out an announcement for opportunities for the Europa mission, scheduled for launch sometime in 2004. It would take anywhere from five to seven years for the instruments to reach Europa, after which time measurements would be taken for about a month. The IPR is one of a suite of instruments--called a strawman's payload--that NASA currently is considering sending to Europa, the other instruments being an optical camera, transponder and laser altimeter. The IPR is the primary instrument; the laser altimeter would be used to measure the tidal bulge of Europa's surface caused by Jupiter's tremendous gravitational pull on the moon. "The laser altimeter will measure the moon's tides. If they're small, then we'll know that there's little or no water underneath the surface," said Edwards. Shao said although it is conceivable that NASA may choose an instrument suite that does not include the IPR for the Europa mission, because the IPR is one of only a few instruments that can both measure Europa's ice surface depth and characterize its structure, there is a good chance that it will remain part of the suite that ultimately makes the 400-million-mile trek. The University of California operates Los Alamos National Laboratory for the U.S. Department of Energy. ------------------------------------------------------------------ FOSSILIZED MAGNETOTACTIC BACTERIUM IN THE ORGUEIL METEORITE By Brig Klyce From Common Ancestry 8 September 1998 In 1966, W. C. Tan and Sam L. VanLandingham examined samples of the Orgueil meteorite. Like the Murchison meteorite, Orgeuil is a carbonaceous chondrite. It was seen as it fell near Orgueil, France, on May 14, 1864. Samples of it have been extensively studied, especially by Bart Nagy, whose photos of lifelike fossils in it were published in Nature, in the early 1960s. The above photo was among several dozen by Tan and VanLandingham of fossils in Orgueil that looked biological to them. It was among a handful published in a very brief article in the Journal of the Royal Astronomical Society, in 1967 (1). In those days, Tan and VanLandingham had no idea what the "filamentary microstructures" like this one might be, because they had never heard of magnetotactic bacteria. Today however, we do know about such bacteria. They ingest and retain iron, which causes them to align themselves with a magnetic field. If enough of them die and become fossilized together, the matrix will be a "natural magnet". Sam VanLandingham says that the Orgueil sample in which the fossil was found had many similar fossils, all neatly aligned, pointing the same way. When seen through a transmission electron microscope, the most striking feature of magnetotactic bacteria is the magnetosomes inside them. These membrane-bound particles of magnetite (iron oxide) appear as dark, regularly spaced inclusions whose geometry and spacing vary from one species to another. (In this example they resemble dark portholes on a tiny submarine.) The picture below shows a typical magnetotactic bacterium, of the species Rhodopseudomonas rutilis. Its size and shape are very similar to those of the fossil above. Most telling, however, is the match in size, shape and spacing of the magnetosomes. In 1998, NASA's Richard Hoover first showed the above photo to Russian bacteriologist Mikhail Vainshtein, who studies magnetotactic bacteria. He recognized it immediately. The photo below came from Vainshtein's collection (2). The fossil from the Orgueil meteorite, photographed in 1966, was first identified as a magnetotactic bacterium like the one in the lower photo only this year. We suggest that this evidence of a fossilized bacterium in a carbonaceous chondrite cannot be easily dismissed. References 1. Tan, W. C. and S. L. VanLandingham. "Electron microscopy of biological-like structures in the Orgueil carbonaceous meteorite," p 237 v 12 Geophys. J. Royal Astr. Soc., 1967. 2. Hoover, Richard; Alexei Yu. Rozanov; S. I. Zhmur and V. M. Gorlenko. "Further Evidence of Microfossils in Carbonaceous Chondrites," in Instruments, Methods, and Missions for Astrobiology, Richard B. Hoover, Editor, Proceedings of SPIE Vol. 3441, p 203-216 (1998). (May be ordered through Proceedings of SPIE.) [Additional information on this article may be found at http://www.panspermia.org/magneto.htm] ------------------------------------------------------------------ GREAT BUGS OF FIRE: PROTEIN FROM VOLCANO-LOVING BUG CRYSTALLIZED IN SPACE By David Noever From NASA Space Science News 16 September 1998 They may be small, but they're very hot. They're the archaea, an ancient branch of microbial life on Earth discovered by scientists in 1977. Unlike the better known bacteria and eukaryotes (plants and animals), many of the archaea can thrive in extreme environments like volcanic vents and acidic hot springs. They can live without sunlight or organic carbon as food, and instead survive on sulfur, hydrogen, and other materials that normal organisms can't metabolize. It may sound like science fiction, but many scientists are working rapidly to explore the biology as well as the practical benefits of these recently discovered life forms. An enzyme, alcohol dehydrogenase (ADH), is derived from a member of the archaea called Sulfolobus solfataricus. It works under some of nature's harshest volcanic conditions. It can survive to 88° C (190°F)--nearly boiling--and corrosive acid conditions (pH=3.5) approaching the sulfuric acid found in a car battery (pH=2). ADH produces ethanol naturally and has considerable potential for biotechnology applications due to its stability under these extreme conditions. To understand how it works, scientists first need to learn its basic structure. For this, an Italian research team went to space. After collecting Sulfolobus solfataricus from the Solfatara volcanic area near Naples, the Italian team purified the ADH enzyme for crystallization aboard the Space Shuttle. Compared to crystals grown in Earth's gravity, the space crystals showed an improved quality of nearly 35%, and the researchers obtained diffraction data with a significantly higher resolution, indicating reduced disorder. Scientists hope to use the space grown crystals to improve the biological understanding of how these molecules work based on a detailed knowledge of their shape and exact atomic positions. A fundamental question posed by the space shuttle investigation is: what features of these volcanic microbes' metabolism allow for such thermal stability in their enzymes? If unusual characteristics in their metabolism can be identified and studied, the transfer of this knowledge is almost immediate to applications in environmental cleanup, pollution prevention, or energy production. Many researchers envision a range of medically, industrially, and environmentally useful compounds derived from the extreme heat-loving, or "hyperthermophilic" Archaea. Biomolecules from these organisms are active at temperatures that generally degrade normal cellular molecules, such as enzymes, lipids, and nucleic acids. When stored at room temperature, these molecules from volcanic microbes are in the "deep freeze" compared to their normal lives, thus offering tremendously extended shelf-life and stability in commercial use. The first Archaea-related products were DNA polymerases for the research market. For example, New England Biolabs, a Beverly, MA- based biotechnology company, sells Vent and Deep Vent polymerases, used in DNA sequencing. These enzymes originally were isolated from hyperthermophiles associated with oceanic hydrothermal vents. Without analysis of these fiery microbes, neither the modern identification of human genetic diseases nor the use of DNA evidence in legal courts would even have been realized. The Archaea Researchers say that the heat and geochemical conditions in volcanic regions may be similar to conditions that existed on the young, water-covered, cooling Earth. Almost like a creature from science fiction, the volcanic microbe is different from the two other basic branches of life: bacteria and eukaryotes. The prokaryotes are the bacteria, while eukaryotes are the so-called higher forms of life, including humans, plants and animals. A major difference is that eukaryotes put their genes inside a nucleus, while prokaryotes do not. In the archaea, there is no nucleus, but many genes behave like those in higher organisms. Archaea are thought to have a common ancestor with bacteria, but billions of years ago the third domain, eukaryotes, broke off from archaea, eventually developing into plants, animals and us. Archaea include microbes that live at the extremes of the planet - the very, very cold, hot or high-pressure places that no other form of life could endure. As such, archaea are the extremophiles who boldly thrive where no other life form would go. Some scientists have suggested that as such, archaea may represent the earliest form of life and thus may be the most likely form of life existing on other planets. About 500 species of archaea are now identified, but speculation may not be far off in projecting that given the difficulties of collecting and classifying them, there may be a million others. The life form is thought to produce about 30 percent of the biomass on Earth, much of it in the Antarctic Ocean. In fact, as far back as 1994, Myrna Watanabe, a biotechnology consultant, wrote that the existence of this third branch of life "here on Earth has led scientists to realize that planets they hitherto assumed to be lifeless might support life." Much work remains to be done in uncovering the shape and detailed way that these extreme microbial molecules achieve their thermal stability. In a controlled study comparing space grown crystals with the best data ever previously obtained from ADH crystals formed on Earth, the Italian team found that the "the microgravity-grown crystals displayed increased stability when exposed to X-rays." This finding moves the investigation closer to revealing the biological function of these complex molecules. According to their report, although future flights will be required to solve the fully three-dimensional picture of the molecule, the Space Shuttle provided larger, more ordered and more radiation-stable examples of this microbial enzyme. [More information concerning this article may be found at http://science.msfc.nasa.gov/newhome/headlines/msad16sep98_1.htm] ------------------------------------------------------------------ NATURE'S "ELECTRONIC INK": RETINAL PROTEIN CRYSTALLIZED ON SPACE MISSION By David Noever From NASA Space Science News 17 September 1998 Anyone who has ever fallen on grass knows that nature has chemicals that are as permanent as ink. At least one of those chemicals holds promise as an "electronic ink" that can be used in improved computer displays. The chemical is bacteriorhodopsin, a purple protein essential to the cell wall of Halobacterium halobium, a mysterious resident of salt marshes and lakes. When nutrients get scarce, this bacteriorhodopsin becomes a light- converting enzyme that keeps the organism's life cycle going. It's a protein powerhouse that in times of famine flips back and forth between purple and yellow colors. If controllable, this could be valuable in computer display panels. In the last 25 years, bacteriorhodopsin has excited a great deal of interest among biochemists, biophysicists, and most recently among companies seeking to build battery-conserving, long-life computer displays. The protein, sometimes called nature's "electronic ink" was grown in orbit on board the Space Shuttle for a scientific team from Justus-Liebig University in Glessen, Germany and the Institute for Physiological Chemistry in Hamburg. Part of the attraction to understanding these light powerhouses is that natural materials often perform very complex functions that cannot be easily obtained from manufactured materials such as semiconductors. They have been optimized for these functions by billions of years of evolution and often perform them better than any human-designed material could. For example, bacteriorhodopsin is an attractive material for all- optical "light" computers because of its two stable protein forms, one purple and one yellow. Shining two lasers of different wavelengths alternately on the protein flips it back and forth between the two colors. Several research groups have already used bacteriorhodopsin as computer memory and as the light-sensitive element in artificial retinas. According to their report, the space crystal was stabilized under microgravity conditions... Further experiments in microgravity, as a favorable environment of improved crystallogenesis, provide additional progress in the investigation of difficult membrane proteins such as bacteriorhodopsin. In nature, this salt-loving, probably ancient, organism undergoes a light-stimulated cycle of protein rearrangements, which can interact photochemically. This may be how similar retinal proteins in the eye allow more evolved organisms to see. Analyzing them on Earth has been difficult because these kinds of complex membrane proteins typically require detergents to make them compatible with biological analysis in water. The cubic-shaped space crystals showed a nearly 20-fold larger volume compared to earth-grown counterparts. In comparing space grown crystals of the bacteriorhodopsin with similar crystals formed on earth, the team found that a favorable environment minimizing gravity might advance the search for new means to reveal the biological function of these complex molecules. The large volume of the space-grown crystals will help scientists read the protein's blueprint and understand how it operates. From this, they hope to develop versions that could be used in future computers. [More information concerning this article may be found at http://science.msfc.nasa.gov/newhome/headlines/msad17sep98_1.htm] ------------------------------------------------------------------ NATURE'S SUGAR HIGH: SPACELAB SUCCESSFULLY CRYSTALLIZES INTENSELY SWEET PROTEIN By David Noever From NASA Space Science News 14 September 1998 Your sweet tooth may get a treat that is literally "out of this world," thanks to experiments aboard the Space Shuttle. A team comprising French and American scientists reports they have crystallized one of the most interesting families of intensely sweet proteins, a natural molecule called thaumatin, isolated from the African Serendipity Berry (Thaumatococcus daniellii). Using otherwise similar crystallizing conditions, the space crystal showed a nearly 25% larger volume compared to its earth- grown counterparts and yielded nearly twice the crystalline order. Scientists hope to use the space-grown crystals to improve the biological understanding of how these molecules work based on detailed knowledge of their shape and exact atomic positions. According to the study, the visual quality of the space crystals "appeared virtually flawless, with no observable imperfections, striations or anomalies." The complex and costly management of human diabetes, obesity, and oral health has spawned a widespread search for natural sugar substitutes that are both non-caloric and safe. The calorie-free thaumatin protein, sometimes called nature's "artificial sweetener" was analyzed by scientists from the University of California, Irvine and the Institute for Molecular Biology in Strasbourg, France. In a control study, the team compared space-grown thaumatin crystals with some previously obtained from on earth in a conventional laboratory. They found that the space crystals provided 30% more real information about the molecule's shape. This moves the investigation closer to revealing the biological function of these complex molecules. According to their report, the space crystals reinforce the conclusion of other reports based on different macromolecules that a microgravity environment provides distinct advantages. In the best of only a few thaumatin crystals grown in microgravity, compared with many more trials conducted on earth, the microgravity grown crystals were consistently and significantly larger, and substantially more defect free. This is the first experiment to produce space crystals by multiple methods, both suggesting the same conclusion: crystals grown in microgravity can be significantly improved in their x-ray diffraction properties when compared with those grown on earth. The natural proteins as a group are the sweetest compounds ever discovered. The sweet taste--which depends on nearly 100 different sensory receptors on the tongue--can be detected in the presence of thaumatin at concentrations well below one part protein molecule per 100 million parts of water. On a scale in which 0 refers to no sweetness, 1 refers to table sugar or sucrose, then thaumatin is nearly off the scale at 3,000, more than 10 times sweeter than other sugar substitutes like saccharin or aspartame. Because these kinds of complex sensory-stimulating proteins typically require binding to specific taste receptors, much of their biology remains to be worked out in the kind of studies done on the space shuttle and using modern tools of biological crystallography. Already within the bulk commercialization by biotechnology companies, Tate & Lyle's product, Talin, is marketed from thaumatin. Also, at the Unilever Research Laboratory in The Netherlands, the gene for this sweetener has been cloned into biological production using the microorganisms E. coli and yeast to substitute for the original African shrub. As a non-caloric sweetener, thaumatin has attracted attention as a candidate for control of obesity, oral health and diabetic management. Thaumatin already is being marketed as a nutritional supplement in blood sugar stabilizers for childhood behavioral problems and the more than 3.5 million sufferers from attention deficit disorder. Among soft drink consumers alone, nearly 20.6 million tons of chemicals are used around the world--nearly 4 kilograms per capita, with a growth of about 20% towards the end of the decade. Control of diabetes, the most common metabolic disease in the world, largely hinges on managing sugar levels in the bloodstream. According to a recent study published in the Journal of Clinical Endocrinology and Metabolism, one out of every seven health care dollars, or $105 billion, goes to the treatment of diabetes- related complications. Individual diabetics spent an average of $9,493 on health care in 1992, the latest data available, compared with $2,604 for people without diabetes, the study said. Nearly 600,000 people per year are diagnosed as diabetic in the US. The National Institutes of Health proved that diabetic patients who can maintain blood-sugar levels as close as possible to normal can significantly slow the disease. Biotechnology in space Some estimates suggest that human biology depends on the action of nearly half a million different enzymes and proteins. In less than 1 case in 100, we have a three-dimensional picture of shape and function of these complex chemicals. Since 1984, the Space Shuttle has carried experiments to determine the structures of large, biologically important molecules. This research has compiled results for a host of human diseases ranging from insulin (for the control of diabetes) to one enzyme called reverse transcriptase that can be blocked to inhibit HIV infection. In comparing more than 33 such different biological molecules crystallized on the Shuttle and also in similar conditions on earth, space produced larger space crystals in 45% of the cases and new structures in nearly 20% of the cases. As many as half the space crystals had a 10% or better improvement in the x-ray brightness or the crystallographic resolution. Both are important to determining these large molecules' shape and exact atomic positions. [More information on this article may be obtained at http://science.msfc.nasa.gov/newhome/headlines/msad14sep98_1.htm] ------------------------------------------------------------------ End Marsbugs Vol. 5, No. 21