J. I. Gitelson

The Chemical Basis of Fungal Bioluminescence

Many species of fungi naturally produce light, a phenomenon known as bioluminescence, however, the fungal substrates used in the chemical reactions that produce light have not been reported. We identified the fungal compound luciferin 3-hydroxyhispidin, which is biosynthesized by oxidation of the precursor hispidin, a known fungal and plant secondary metabolite. The fungal luciferin does not share structural similarity with the other eight known luciferins. Furthermore, it was shown that 3-hydroxyhispidin leads to bioluminescence in extracts from four diverse genera of luminous fungi, thus suggesting a common biochemical mechanism for fungal bioluminescence.

Consistency of gas exchange of man and plants in a closed ecological system: lines of attack on the problem.

Gas exchange between man and plants in a closed ecological system based on atmosphere regeneration by plant photosynthesis is made consistent by attaining the equilibrium of human CO2 discharge and the productivity of the gas consuming bioregenerator. In this case the gas exchange might be, however, qualitatively disturbed from the equilibrium in terms of oxygen making it accumulate or decrease continuously in the air of the system. Gas exchange equilibrium in terms of O2 was attained in long-term experiments by equality of the human respiration coefficient and the plant assimilation coefficient. Varying the ratio of these parameters it is possible to control the oxygen concentration in the atmosphere to be reclaimed.

Effect of volatile metabolites of dill, radish and garlic on growth of bacteria

In a model experiment plants were grown in sealed chambers on expanded clay aggregate under the luminance of 150 W/m2 PAR and the temperature of 24 degrees C. Seven bacterial strains under investigation, replicated on nutrient medium surface in Petri dishes, were grown in the atmosphere of cultivated plants. Microbial response was evaluated by the difference between colony size in experiment and in control. In control, bacteria grew in the atmosphere of clean air. To study the effects of volatile metabolites of various plant on microbial growth, the experimental data were compared with the background values defined for each individual experiment. Expanded clay aggregate, luminance, temperature, and sealed chamber (without plants) for the background were the same. Volatile metabolites from 28-days old radish plants have been reliably established to have no effect on the growth of microbes under investigation. Metabolites of 30-days old dill and 50-days old garlic have been established to have reliable bacteriostatic effect on the growth of three bacterial strains. Dill and garlic have been found to have different range of effects of volatile substances on bacterial growth. Volatile metabolites of dill and garlic differed in their effect on the sensitivity spectrum of bacteria. An attempt has been made to describe the obtained data mathematically.

Mechanism and color modulation of fungal bioluminescence

Study of fungal bioluminescence mechanisms generates development of a multicolor enzymatic chemiluminescence system. Bioluminescent fungi are spread throughout the globe, but details on their mechanism of light emission are still scarce. Usually, the process involves three key components: an oxidizable luciferin substrate, a luciferase enzyme, and a light emitter, typically oxidized luciferin, and called oxyluciferin. We report the structure of fungal oxyluciferin, investigate the mechanism of fungal bioluminescence, and describe the use of simple synthetic α-pyrones as luciferins to produce multicolor enzymatic chemiluminescence. A high-energy endoperoxide is proposed as an intermediate of the oxidation of the native luciferin to the oxyluciferin, which is a pyruvic acid adduct of caffeic acid. Luciferase promiscuity allows the use of simple α-pyrones as chemiluminescent substrates.

Closed Ecological Systems, Space Life Support and Biospherics

This chapter explores the development of a new type of scientific tool – man-made closed ecological systems. These systems have had a number of applications within the past 50 years. They are unique tools for investigating fundamental processes and interactions of ecosystems. They also hold the potentiality for creating life support systems for space exploration and habitation outside of Earth’s biosphere. Finally, they are an experimental method of working with small “biospheric systems” to gain insight into the functioning of Earth’s biosphere. The chapter reviews the terminology of the field, the history and current work on closed ecological systems, bioregenerative space life support and biospherics in Japan, Europe, Russia, and the United States where they have been most developed. These projects include the Bios experiments in Russia, the Closed Ecological Experiment Facility in Japan, the Biosphere 2 project in Arizona, the MELiSSA program of the European Space Agency as well as fundamental work in the field by NASA and other space agencies. The challenges of achieving full closure, and of recycling air and water and producing high-production crops for such systems are discussed, with examples of different approaches being used to solve these problems. The implications for creating sustainable technologies for our Earth’s environment are also illustrated.

Chemiluminescent emission of tissues of fruit bodies of higher fungi

105 Among the dozens of thousands of species of higher fungi known to date, more than 80 species possess bioluminescence—the ability to emit light that is visii ble with the naked eye. This ability was found in the to note that the luminescent species phylogenetically coexist with the nonluminescent ones. Sometimes even one taxonomically defined species includes both luminescent and nonluminescent forms [2, 3]. Such a mosaic distribution of bioluminescence suggests that the ability to luminesce has occurred in the kingdom of fungi repeatedly and independently and that its evolutionary basis is a fundamental bioo chemical process, a small deviation in which (even in one or two stages of the metabolic chain) gives rise to luminescence. However, such a process remains unree vealed as yet. The absence of intermediate forms makes it highly difficult to elucidate the evolutionary pathway of the emergence of bioluminescence in the kingdom of fungi. Although the notions on the mechanism of light emission by fungi are far from complete [3, 4], it is obviously distinct from the understood emission mechanisms in animals and bacteria. Weak chemiluu minescence is characteristic of animal tissues [5]. It is known that the major source of luminescence in animals is lipid peroxidation [6] and that chemilumii nescence in plants is related to the photosynthesis system [7]. We studied the emission of nonbioluminescent higher fungi. Studies were performed with different species of higher fungi growing in forests of the Eastt ern Siberian region of Russia (Krasnoyarsk Krai). The objects of the study were 150 samples of fungi collected in forests in vicinities of Krasnoyarsk in summer 2011. The collections were representatives of five orders, 15 families, 21 genera, and 13 species. As many as 136 samples of the collected material were identified to the genus level and 35 samples to the species level (table). We measured luminescence of fungal fragments taken from different parts of the fruit body. Measuree ments were performed with the Glomax 20/20 lumii nometer (Promega, United States), which was calii brated using the Hastings–Weber radioactive standard [8] (2.7 × 10 3 quanta/s was taken as one unit of lumii nescence). The emission of each sample was recorded for 10 s. Signals exceeding the background level by at least 5 times were taken as reliable. Then, each sample was air dried to a constant weight to calculate the spee cific luminosity per unit mass. The table shows the …

Indications and counterindications for applying different versions of closed ecosystems for space and terrestrial problems of life support.

Different versions of manned closed ecosystems (CES) based on photosynthesis of unicellular and/or higher plants and chemosynthesis or bacteria are considered. Different versions of CES have been compared for applying them on Earth, Moon, Mars and Venus orbital stations, for Mars missions and planetary stations as well as to provide high-quality life in extreme conditions on the Earth. In microgravity [correction of mycrogravity] we recommend CES with unicellular organisms based on photosynthesis or chemosynthesis (depending of the availability of the light or electric energy). For the planetary stations with Moon gravity and higher CES with higher plants are recommended. Improvement of indoor air quality by CES biotechnology is considered.

Why does the bioluminescent fungus Armillaria mellea have luminous mycelium but nonluminous fruiting body

By determining the components involved in the bioluminescence process in luminous and nonluminous organs of the honey fungus Armillaria mellea, we have established causes of partial luminescence of this fungus. The complete set of enzymes and substrates required for bioluminescence is formed only in the mycelium and only under the conditions of free oxygen access. Since the synthesis of luciferin precursor (hispidin) and 3-hydroxyhispidin hydroxylase in the fruiting bodies is blocked, the formation of luciferin—the key component of fungal bioluminescent system—was not observed. That is why the fruiting body of Armillaria mellea is nonluminous despite the presence of luciferase, the enzyme that catalyzes the oxidation of luciferin with a photon emission.

The health of biological life support systems

Abstract In developing different types of biological life support systems for use in space or extreme environments on Eart, researchers should pay attention to the long term health or functional state of such systems. The difficulty of the task is compounded by the complexity of the links and structure to be found in biological systems. To solve the problem, a hierarchical approach may be used to estimate and monitor the health of the system as a whole and its individual links. Three levels in a typical hierarchy have been considered: 1. a. the organismic. 2. b. populations and communities. 3. c. the ecosystem. Special attention has been given to the interactions between macro- and microorganisms. Microorganisms are considered the most suitable indicators of a systems health and its component links.

Isolation and Purification of Fungal Luciferase from Neonothopanus nimbi

This is the first study to obtain a high-purity luciferase from the fungus Neonothopanus nambi biomass that is suitable for subsequent sequencing.