RESUMEN
Capacity of AG(S10), a new aerobic acidophilic (growing within the pH range from 1.3 to 4.5 with the optimum at 2.0-2.5) bacterial association from sulfur blocks of the Astrakhan gas-processing complex (AGC), for oxidation of hydrocarbons of various chemical structure was investigated. A broad spectrum of normal (C10-C21) and iso-alkanes, toluene, naphthalene, andphenanthrene, as well as isoprenoids resistant to microbial degradation, pristane and phytane (components of paraffin oil), and 2,2,4,4,6,8,8,-heptamethylnonane, a branched hydrocarbon, were biodegraded under acidic conditions. Microbiological investigation revealed the dominance of mycobacteria in the AGS10 association, which was confirmed by analysis of the 16S rRNA gene clone library. In the phylogenetic tree, the 16S rRNA sequences formed a branch within the cluster of slow-growing mycobacteria, with 98% homology to the closest species Mycobacterium florentinum. Genomic DNA of AG(S10) culture grown on C14-C17 n-alkanes at pH 2.5 was found to contain the genes of two hydroxylase families, alkB and Cyp 153, indicating their combined involvement in hydrocarbon biodegradation. The high hydrocarbon-oxidizing potential of the AGS10 bacterial association, indicated that further search for the genes responsible for degradation of various hydrocarbons in acidophilic mycobacteria could be promising.
Asunto(s)
Alcanos/metabolismo , Hidrocarburos/metabolismo , Consorcios Microbianos/fisiología , Filogenia , Alcanos/química , Biodegradación Ambiental , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Consorcios Microbianos/genética , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Datos de Secuencia Molecular , Mycobacterium/genética , Mycobacterium/fisiología , Aceites , Oxidación-Reducción , Parafina , Petróleo , ARN Ribosómico 16SRESUMEN
Goals of the 3-month experiment GREENHOUSE using the equipment of greenhouse SVET (ECO-PSY-95) were to feature growth and development of wheat through the entire cycle of ontogeny under the maximally mimicked MIR environment, and to try out the procedures and timeline of space experiment GREENHOUSE-2 as a part of the fundamental biology investigations within the MIR/NASA space science program. Irradiation intensity (PAR) was 65 W/m2 and 38 W/m2 in the experiment and laboratory control, respectively. Values of other environmental parameters were MIR average (18-25 degrees C, relative air humidity in the interval between 40% and 75%, total gas pressure of about 660 to 860 mm Hg, partial oxygen pressure within the range from 140 to 200 mm Hg, partial carbon dioxide pressure up to 7 mm Hg). Experimental results showed that wheat cultivation in inhabited chamber under a modified lighting unit providing greater irradiation of the crop area produced more plant mass although seed production dropped. Low grain content in ears could be the aftermath of the gaseous trace contaminants in the chamber atmosphere.
Asunto(s)
Simulación del Espacio , Nave Espacial , Triticum/crecimiento & desarrollo , Presión del Aire , Exposición a Riesgos Ambientales , Estudios de Seguimiento , Humedad , Luz , Hojas de la Planta/crecimiento & desarrollo , TelemetríaRESUMEN
The effect of space flight factors on the growth and development of wheat grown in a Svetoblock-M unit on the orbital station Mir was investigated. The data obtained allow the conclusion that wheat plants develop flight-induced changes. When compared to control plants, experimental plants show a delayed growth in terms of biometric parameters, different distribution of biogenic elements, lower phytoncidal activity, increased bacterial and fungal contamination, and a changed pigment and lipid composition.
Asunto(s)
Vuelo Espacial , Triticum/crecimiento & desarrolloRESUMEN
This paper discusses the functional characteristics of the man-plant-mineralization system and the environment it forms when it is supplemented with a photoautotrophic component including higher plants and algae. The functional characteristics of the higher plant component were studied when it operated first in an independent cultivation mode, then coupled with a biological system of human and biocomplex waste mineralization, and finally with a human gas exchange system and Chlorella containing photosynthetic reactors. This approach demonstrated for the first time that Chlorella and higher plants can normally work in a common autosphere. The paper also presents quantitative data about the use of higher plants in a biological life support system. Data analysis shows that the total plant yield did not diminish when the system was closed and man, mineralization system and algal reactors were connected. However although the total photosynthetic productivity remained unchanged, the yield of useful crops decreased. This points to a complex nature of the above effects, the causes of which remain so far inexplicable and require further study.