Mycology studies in space

Summary The postflight phase of the Apollo MEED mycology attempts to identify survival according to exposure to specific quantitative space flight factors, while the second phase of studies identifies qualitative change other than cell survival [57]. Initial changes incurred in space on a fungal cell can be monitored and further examined on return of the fungal species test system to Earth. The postflight studies present a better understanding of the space environmental influences on living cells and a more clear understanding of the fungal species under examination.Presented as part of the Everett S. Beneke Symposium in Mycology, May 27, 1988.     

Phosphoglycerides of Trichophyton terrestre and One Phenotype Selected from the Apollo 16 Microbial Ecology Evaluation Device

Total lipid extracted from wild-type Trichophyton terrestre CDC-X285 was found to be 2.0 percent of the dry cell weight. The total lipid contained the following phospholipid components identified by silicic acid-impregnated thin-layer and paper chromatography: phosphatidyl inositol, phosphatidyl choline, phosphatidyl serine, and phosphatidic acid. The total lipid extracted from the phenotype T. terrestre 7048-1 isolated from the Apollo 16 Microbial Ecology Evaluation Device (MEED) was found to vary according to the time at which the phospholipids were extracted. The Trichophyton phenotype was selected from a cuvette housed in the MEED exposed to specific space parameters including ultraviolet light of known wavelengths and energy levels in deep space. The phospholipid components, identified in the phenotype were phosphatidyl ethanolamine and cardiolipin. The major lipid fraction was composed of digalactosyl diglyceride and monogalactosyl diglyceride. An unusual lipid was detected in the phenotype, which appeared to be sterol glycoside.     

Effect of cytochrome oxidase inhibitors on the yeast thermotolerance

The investigation of the effect of the cytochrome oxidase inhibitors sodium cyanide and sodium azide on the thermotolerance of the yeasts Rhodotorula rubra, Debaryomyces vanriji, and Saccharomyces cerevisiae showed that these inhibitors diminish the thermotolerance of R. rubra and D. vanriji, but do not affect the thermotolerance of S. cerevisiae. Taking into account the fact that, unlike the latter yeast, R. rubra and D. vanriji are nonfermentative yeasts, the difference in the effects of the inhibitors on the yeast thermotolerance can be readily explained by the different types of glucose utilization (either oxidative or fermentative) in these yeasts. The data obtained also provide evidence that there is a correlation between the functional activity of mitochondria and the thermotolerance of yeast cells.     

The antifungal activity of normal and host-compromised saliva on spaceflight fungal phenotypes

Phenotypic variants of parent strains ofChaetomium globosum, Trichophyton terrestre, Rhodotorula rubra, andSaccharomyces cerevisiae were exposed to pooled salivary samples contributed by healthy individuals and three groups of outpatients receiving radiation treatment for malignancies, protracted corticosteroid regimes for renal complications, and insulin therapy for diabetes mellitus. Significant variations occurred in fungal growth rates according to phenotype association with specific salivary samples.     

Sensitivity of heat-stressed yeasts to essential oils of plants.

Eight strains of yeasts (Candida lipolytica, Debaryomyces hansenii, Hansenula anomala, Kloeckera apiculata, Lodderomyces elongisporus, Rhodotorula rubra, Saccharomyces cerevisiae, and Torulopsis glabrata) were examined for changes in sensitivity to eight essential oils of plants (allspice, cinnamon, clove, garlic, onion, oregano, savory, and thyme) after being sublethally heat stressed. With the exception of garlic oil for all test yeasts, onion oil for S. cerevisiae, and oregano oil for R. rubra, the essential oils at concentrations of up to 200 ppm in recovery media did not interfere with colony formation by unheated cells. However, some oils, at concentrations as low as 25 ppm in recovery media, reduced populations of sublethally heat-stressed cells compared to populations recovered in media containing no test oils. This demonstrates that the yeasts were either metabolically or structurally damaged as a result of being exposed to elevated temperatures and that essential oils prohibited repair of injury. The size (diameter) of colonies produced on oil-supplemented recovery agar by heat-stressed cells was reduced compared to that observed on unsupplemented agar. Pigment production by heated R. rubra was inhibited by oils of oregano, savory, and thyme, but enhanced by garlic and onion oils. The influence of essential oils on survival of yeasts in thermally processed foods and in the enumeration of stressed cells in these foods should not be minimized.     

Experimental pathogenicity ofSporothrix schenckii preserved in water (Castellani)

Five strains ofSporothrix schenckii preserved in sterile destillated water were found morphologically stable, viable and pure after a period ranging from 16 to 13 years, in the mycology section culture collection from the Instituto de Medicina Tropical, Universidad Central de Venezuela. Each strain was inoculated into the testes of 3 hamsters. All the animals developed disseminated sporotrichosis.     

The microbial ecology evaluation Device mycology spaceflight studies of Apollo 16

Four fungal species were selected as the test systems for the Microbial Ecology Evaluation Device (MEED) of Apollo 16. Fungal cells were exposed to various quantitative and qualitative spaceflight parameters then returned for postflight analyses. Survival rates and phenotype numbers varied according to exposure parameters. Additional studies underway will further identify the spaceflight changes.     

Changes in a salt-marsh vegetation as a result of grazing and mowing — A five-year study of permanent plots

Summary Part of a salt-marsh (32 ha), ungrazed from 1958 until 1971, was grazed again from 1972 onwards with young cattle (1.3–1.7 per ha, May–October). In five vegetation types management experiments, including doing nothing (control). June mowing, August mowing, June and August mowing, all in combination or not in combination with grazing have been started with the objective to compare annually their effects on the vegetational structure and composition by means of permanent plots (2×2 m).Thirteen years (1958–1971) after the grazing had ceased the vegetation types of Festuca rubra/Armeria maritima, Artemisia maritima, Juncus maritimus and Elytrigia pungens hardly changed anymore. The vegetation type of Festuca rubra/Limonium vulgare, changed considerably. The experiments showed rather specific effects during the period 1971–1975 for each type of vegetation. Changes in the Festuca rubra/Armeria maritima vegetation were small and gradually under all treatments. Changes in The Artemisia maritima, Festuca rubra/Limonium vulgare and Juncus maritimus vegetation types were rather great under the different grazing treatments, the changes being abrupt and especially taking place in the third and fourth year of the experiments. The Elytrigia pungens vegetation showed large changes under all treatments, except the control plot, whereas these changes were abrupt, particularly occurring in the first and second year of the experiments. The study is continued.Nomenclature of taxa follows Heukels & van Ooststroom (1970), that of syntaxa Westhoff & den Held (1969).Contribution to the Symposium of the Working Group for Succession research on permanent plots of the International Society for Vegetation Science, held at Yerseke, the Netherlands, October 1975.Thanks are due to Prof. Dr. D. Bakker for his interest in the present study and his critical reading of the text, and to Drs D.C.P. Thalen for critical reading and correction of the English text. Thanks are also due to the students who analyzed the permanent plots: M. van der Duim and F. Prins (1971), M. van der Duim (1972), R. Schwab and T. Schwab-Vos (1973), and G. Allersma (1974, 1975).     

How ants find each other; temporal and spatial patterns in nuptial flights

Reproduction is a key factor in understanding population ecology and therefore species occurrence. However, patterns in reproductive behaviour for distinct ant species remain insufficiently known. In this paper strategies in mate finding are studied for six ant species (Lasius niger, Lasius umbratus, Temnothorax nylanderi, Myrmica rubra, Myrmica ruginodis, Stenamma debile) in a forest – forest edge – agricultural field gradient. Using window traps, we studied whether these species had a restricted nuptial flight season, displayed swarming behaviour, and whether the alates aggregated at the forest edge. The flight season was limited to one month or less for L. niger, T. nylanderi, M. rubra, M. ruginodis and S. debile. Swarming behaviour occurred in all but one (L. umbratus) species. Although none of the six species seemed to have highest nest density at the forest edge, three of them, M. rubra, M. ruginodis and S. debile, showed male aggregations there, indicating this to be the main reproduction site. This last finding could be due to a more suitable micro-climate, but most likely, edges are conspicuous land marks which are used by ants to meet mates. The behavioural patterns of ant sexuals at the forest edge can influence dispersal possibilities in fragmented landscapes, reproductive success and nest densities. Received 27 November 2007; revised 27 March; accepted 5 April 2008.     

Space flight effects on haemopoietic stem cells of the bone marrow of rats

Abstract. Changes in the number of haemopoietic stem cells (CFU-s) were studied in rats during the recovery day and selected post-recovery days after an 18–19-day flight on biosatellites Cosmos 936 and Cosmos 1129 . There was a decrease in the CFU-s number of the bone marrow of rats on the recovery day. On the 6th day post-recovery the CFU-s number was still depressed, while on the 25th day post-recovery it was elevated above control value. The differentiation ratio of transplanted bone marrow cells was not altered by space flight.     

Giant peroxisomes in oleic acid-induced Saccharomyces cerevisiae lacking the peroxisomal membrane protein Pmp27p

We have purified peroxisomal membranes from Saccharomyces cerevisiae after induction of peroxisomes in oleic acid-containing media. About 30 distinct proteins could be discerned among the HPLC- and SDS-PAGE- separated proteins of the high salt-extracted peroxisomal membranes. The most abundant of these, Pmp27p, was purified and the corresponding gene PMP27 was cloned and sequenced. Its primary structure is 32% identical to PMP31 and PMP32 of the yeast Candida biodinii (Moreno, M., R. Lark, K. L. Campbell, and M. J. Goodman. 1994. Yeast. 10:1447-1457). Immunoelectron microscopic localization of Pmp27p showed labeling of the peroxisomal membrane, but also of matrix-less and matrix containing tubular membranes nearby. Electronmicroscopical data suggest that some of these tubular extensions might interconnect peroxisomes to form a peroxisomal reticulum. Cells with a disrupted PMP27 gene (delta pmp27) still grew well on glucose or ethanol, but they failed to grow on oleate although peroxisomes were still induced by transfer to oleate- containing media. The induced peroxisomes of delta pmp27 cells were fewer but considerably larger than those of wild-type cells, suggesting that Pmp27p may be involved in parceling of peroxisomes into regular quanta. delta pmp27 cells cultured in oleate-containing media form multiple buds, of which virtually all are peroxisome deficient. The growth defect of delta pmp27 cells on oleic acid appears to result from the inability to segregate the giant peroxisomes to daughter cells.     

Penetration of Trichophyton terrestre in human hair

The systematic human hair degradation by Trichophyton terrestre was examined by electron and light microscopy. The cuticular and hair shaft regions were readily decomposed by the wild type or parent strain selected for phenotype studies after exposure to spaceflight parameters.     

卫星搭载啤酒酵母糖代谢相关酶类活性变化

分析了搭载于实践八号育种卫星的啤酒酵母的存活情况和糖代谢相关酶类活性。啤酒酵母于YPD液体培养基培养,培养过夜后用新鲜YPD稀释106倍,分装后分别置于地面和卫星搭载两种条件下15d。返回地面后收集样品,利用稀释平板计数法检测啤酒酵母活力,采用酶解结合分光光度法检澳4酵母糖原水平,分光光度法检测己糖激酶、琥珀酸脱氢酶和苹果酸脱氢酶的活性。结果发现,卫星搭载样品的菌落形成数显著高于地面对照组,卫星搭载样品是地面对照的3．1倍;卫星搭载啤酒酵母样品的己糖激酶和琥珀酸脱氢酶活性均明显低于地面对照组,而卫星搭载样品的苹果酸脱氢酶活性明显高于地面对照组;卫星搭载样品的糖原水平均低于相对应的地面对照组。表明,太空飞行下可导致啤酒酵母的存活率提高,同时伴有糖代谢相关酶活性和糖原水平的变化,提示太空飞行条件下引起糖代谢变化有利于啤酒酵母存活。     

Detection of Renal Tissue and Urinary Tract Proteins in the Human Urine after Space Flight

The urine protein composition samples of ten Russian cosmonauts (male, aged of 35 up to 51) performed long flight missions and varied from 169 up to 199 days on the International Space Station (ISS) were analyzed. As a control group, urine samples of six back-up cosmonauts were analyzed. We used proteomic techniques to obtain data and contemporary bioinformatics approaches to perform the analysis. From the total number of identified proteins (238) in our data set, 129 were associated with a known tissue origin. Preflight samples contained 92 tissue-specific proteins, samples obtained on Day 1 after landing had 90 such proteins, while Day 7 samples offered 95 tissue-specific proteins. Analysis showed that consistently present proteins in urine (under physiological conditions and after space flight) are cubilin, epidermal growth factor, kallikrein-1, kininogen-1, megalin, osteopontin, vitamin K-dependent protein Z, uromodulin. Variably present proteins consists of: Na(+)/K(+) ATPase subunit gamma, β-defensin-1, dipeptidyl peptidase 4, maltasa-glucoamilasa, cadherin-like protein, neutral endopeptidase and vascular cell adhesion protein 1. And only three renal proteins were related to the space flight factors. They were not found in the pre-flight samples and in the back-up cosmonaut urine, but were found in the urine samples after space flight: AFAM (afamin), AMPE (aminopeptidase A) and AQP2 (aquaporin-2). This data related with physiological readaptation of water-salt balance. The proteomic analysis of urine samples in different phases of space missions with bioinformation approach to protein identification provides new data relative to biomechemical mechanism of kidney functioning after space flight.     

Accumulation of a tumor suppressor p53 protein in rat muscle during a space flight

We previously reported that the space environment consisting of microgravity and space radiation induced an increased level of p53 protein, a tumor suppressor gene product, in rat skin. Here, we report the increase of p53 protein in the muscles of rats that traveled into space. Rats were divided into three groups. The first group remained on earth (VC), and did not show any change in p53 protein level. The second group made a 14-day flight into space on the Second Spacelab Life Science (SLS-2) Mission (F). The third group was experimentally subjected to the same kinds of stress as those in the second group without making a space flight (SC). F and SC rats were sacrificed on day zero (F-0, SC-0) and day nine (F-9, SC-9) after return from space. F-0 rats showed a 1.5-fold increase in p53 protein level compared with that of SC-0 rats, whereas, F-9 rats showed a 1.35-fold increase in p53 protein compared with that of SC-9 rats. These results suggest that the accumulation of cellular p53 protein induced by space environments occurs not only in rat skin cells, but also in rat muscle cells.     

Autoflora in the upper respiratory tract of Apollo astronauts.

The typical microbial inhabitants of the oral and nasal cavities of Apollo astronauts were identified before space flight and generally found to be similar to those previously reported for healthy male adults. Additional analyses of samples collected immediately after return of the Apollo 13, 14, 15, and 16 crew members to earth were performed to evaluate the effects of space travel on the microbial bioburden of the upper respiratory tract. In-flight cross-contamination and buildup of pathogens such as Staphylococcus aureus were noted, although significant increases in nonpathogenic species were absent. Other proposed alterations, such as dysbacteriosis (flooding of the mouth with a single species) and simplification of the autoflora, did not occur. Generally, the incidence and quantitation of each species after flight was within the preflight range, although the number of viable Haemophilus cells recovered from the mouth decreased significantly after space flight. Except for those minor alterations listed above, the aerobic and anaerobic bacterial components of the upper respiratory autoflora of Apollo astronauts was found to be stable after space flight of up to 295 h.     

Mitochondrial NADH-cytochrome b(5) reductase plays a crucial role in the reduction of D-erythroascorbyl free radical in Saccharomyces cerevisiae.

The relevance of NADH-cytochrome b(5) reductase to the NADH-dependent reduction of D-erythroascorbyl free radical was investigated in Saccharomyces cerevisiae. MCR1, which is known to encode NADH-cytochrome b(5) reductase in S. cerevisiae, was disrupted by the insertion of URA3 gene into the gene of MCR1. In the mcr1 disruptant cells, the activity of NADH-D-erythroascorbyl free radical reductase almost disappeared and the intracellular level of D-erythroascorbic acid was about 11% of that of the congenic wild-type strain. In the transformant cells carrying MCR1 in multicopy plasmid, the intracellular level of D-erythroascorbic acid and the activity of NADH-D-erythroascorbyl free radical reductase increased up to 1.7-fold and 2.1-fold, respectively. Therefore, it indicated that the MCR1 product, mitochondrial NADH-cytochrome b(5) reductase, plays a key role in the NADH-dependent reduction of D-erythroascorbyl free radical in S. cerevisiae. On the other hand, the mcr1 disruptant cells were hypersensitive to hydrogen peroxide and menadione, and overexpression of MCR1 made the cells more resistant against oxidative stress. These results suggested that the mitochondrial NADH-cytochrome b(5) reductase functions as NADH-D-erythroascorbyl free radical reductase and plays an important role in the response to oxidative damage in S. cerevisiae.     

Effects of space flight on GLUT-4 content in rat plantaris muscle

 The effects of 14 days of space flight on the glucose transporter protein (GLUT-4) were studied in the plantaris muscle of growing 9-week-old, male Sprague Dawley rats. The rats were randomly separated into five groups: pre-flight vivarium ground controls (PF-VC) sacrificed approximately 2 h after launch; flight groups sacrificed either approximately 5 h (F-R0) or 9 days (F-R9) after the return from space; and synchronous ground controls (SC-R0 and SC-R9) sacrificed at the same time as the respective flight groups. The flight groups F-R0 and F-R9 were exposed to micro-gravity for 14 days in the Spacelab module located in the cargo bay of the shuttle transport system – 58 of the manned Space Shuttle for the NASA mission named ”Spacelab Life Sciences 2”. Body weight and plantaris weight of SC-R0 and F-R0 were significantly higher than those of PF-VC. Neither body weight nor plantaris muscle weight in either group had changed 9 days after the return from space. As a result, body weight and plantaris muscle weight did not differ between the flight and synchronous control groups at any of the time points investigated. The GLUT-4 content (cpm/μg membrane protein) in the plantaris muscle did not show any significant change in response to 14 days of space flight or 9 days after return. Similarly, citrate synthase activity did not change during the course of the space flight or the recovery period. These results suggest that 14 days of space flight does not affect muscle mass or GLUT-4 content of the fast-twitch plantaris muscle in the rat. Received: 25 March 1997 / Accepted: 18 August 1997     

Analysis of deletion mutations of the rpsL gene in the yeast Saccharomyces cerevisiae detected after long-term flight on the Russian space station Mir

Using the yeast Saccharomyces cerevisiae on board the Russian space station Mir, we studied the effects of long-term space flight on mutation of the bacterial ribosomal protein L gene (rpsL) cloned in a yeast-Escherichia coli shuttle vector. The mutation frequencies of the cloned rpsL gene on the Mir and the ground (control) yeast samples were estimated by transformation of E. coli with the plasmid DNAs recovered from yeast and by assessment of the conversion of the rpsL wild-type phenotype (Sm(S)) to its mutant phenotype (Sm(R)). After a 40-day space flight, some part of space samples gave mutation frequencies two to three times higher than those of the ground samples. Nucleotide sequence analysis showed no apparent difference in point mutation rates between the space and the ground mutant samples. However, the greater part of the Mir mutant samples were found to have a total or large deletion in the rpsL sequence, suggesting that space radiation containing high-linear energy transfer (LET) might have caused deletion-type mutations.