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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

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That capacity, self-cleaning is the capacity of a river to clean its water from pollutants over a given length of water course [16].?

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KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for enzyme (Keyword) returned 7 results for the whole karstbase:
Genetic Population Structure in an Amphipod Species., 1981, Golladay S. W. , Gooch James L.
Genetic structure of a species should conform, in part, to environmental structure. Three polymorphic enzyme loci in the amphipod Gammarus minus Say are geographically differentiated in gene frequencies in the mid-Appalachian Mountains of the eastern United States, and genetic breaks usually coincide with topographical features and stream divides. Considering alleles as migrational markers, it is expected that heterozygosity would decrease upstream in isolated drainage basins, increase in the headwaters of adjacent but oppositely flowing streams in which gene exchange was occurring between genetically differentiated populations, and increase in sites near regional master streams. These genetic patterns were found to exist in an area near the Juniata River in central Pennsylvania.

Genetic Differentiation in Populations of the Freshwater Amphipod Gammarus minus Say in a Karst Area., 1981, Gooch James L. , Hetrick Steven W.
The genetic makeup of populations in a particular geographic area should conform, in part, to environmental structure. Three polymorphic enzyme loci in the amphipod Gammarus minus are geographically differentiated in gene frequencies in the mid-Appalachian Mountains of the eastern United States, and genetic breaks usually coincide with topographical features and stream divides. Areas with well integrated drainage systems have a high degree of genetic uniformity.

The kinetics of the reaction CO2?>H? as one of the rate limiting steps for the dissolution of calcite in the system H2O-CO2-CaCO3, 1996, Dreybrodt W, Lauckner J, Liu Zh, Svensson U, Buhmann D,
Dissolution of CaCO3 in the system H2O-CO2-CaCO3 is controlled by three rate-determining processes: The kinetics of dissolution at the mineral surface, mass transport by diffusion, and the slow kinetics of the reaction H2O CO2 = H HCO3-. A theoretical model of Buhmann and Dreybrodt (1985a,b) predicts that the dissolution rates depend critically on the ratio V/A of the volume V of the solution and the surface area A of the reacting mineral. Experimental data verifying these predictions for stagnant solutions have been already obtained in the range 0.01 cm < V/A < 0.1 cm. We have performed measurements of dissolution rates in a porous medium of sized CaCO3 particles for V/A in the range of 2 . 10(-4) cm and 0.01 cm in a system closed with respect to CO2 using solutions pre-equilibrated with an initial partial pressure of CO2 of 1 . 10(-2) and 5 . 10(-2) atm. The results are in satisfactory agreement with the theoretical predictions and show that especially for V/A < 10(-3) cm dissolution is controlled entirely by conversion of CO2 into H and HCO3-, whereas in the range from 10(-3) cm up to 10(-1) cm both CO2-conversion and molecular diffusion are the rate controlling processes. This is corroborated by performing dissolution experiments using 0.6 mu molar solutions of carbonic anhydrase, an enzyme enhancing the CO2-conversion rates by several orders of magnitude. In these experiments CO2 conversion is no longer rate limiting and consequently the dissolution rates of CaCO3 increase significantly. We have also performed batch experiments at various initial pressures of CO2 by stirring sized calcite particles in a solution with V/A = 0.6 cm and V/A = 0.038 cm. These data also clearly show the influence of CO2-conversion on the dissolution rates. In all experiments inhibition of dissolution occurs close to equilibrium. Therefore, the theoretical predictions are valid for concentrations c less than or equal to 0.9 c(eq). Summarising we find good agreement between experimental and theoretically predicted dissolution rates. Therefore, the theoretical model can be used with confidence to find reliable dissolution rates from the chemical composition of a solution for a wide field of geological applications

Precipitation kinetics of calcite in the system CaCO3-H2O-CO2: The conversion to CO2 by the slow process H?->CO2? as a rate limiting step, 1997, Dreybrodt W, Eisenlohr L, Madry B, Ringer S,
Precipitation rates of CaCO3 from supersaturated solutions in the H2O - CO2 - CaCO3 system are controlled by three rate-determining processes: the kinetics of precipitation at the mineral surface, mass transport of the reaction species involved to and from the mineral surface, and the slow kinetics of the overall reaction HCO3- H --> CO2 H2O. A theoretical model by Buhmann and Dreybrodt (1985a,b) taking these processes into account predicts that, due to the slow kinetics of this reaction, precipitation rates to the surface of CaCO3 minerals depend critically on the ratio V/A of the volume V of the solution to the surface area A of the mineral in contact with it, for both laminar and turbulent flow. We have performed measurements of precipitation rates in a porous medium of sized particles of marble, limestone, and synthetic calcite, with V/A ratios ranging from 3.10(-4) to 1.2-10(-2) cm at 10 degrees C. Calcite was precipitated from supersaturated solutions with [Ca2] approximate to 4 mmol/L and an initial P-CO2 of 5.10(-3) or 1.10(-3) atm, respectively, using experimental conditions which prevented exchange of CO2 with the atmosphere, i.e., closed system. The results are in qualitative agreement with the theoretical predictions. Agreement with the observed data, however, is obtained by modifying the rate law of Plummer et al. (1978) to take into account surface-controlled inhibition effects. Experiments with supersaturated solutions containing carbonic anhydrase, an enzyme which enhances the conversion of HCO3- into CO2, yield rates increased by a factor of up to 15. This provides for the first time unambiguous experimental evidence that this reaction is rate limiting. We have also measured precipitation rates in batch experiments, stirring sized mineral particles in a solution with V/A ranging from 0.03 to 0.75 cm. These experiments also give clear evidence on the importance of the conversion of HCO3- into CO2 as rate limiting step. Taken together our experiments provide evidence that the theoretical model of Buhmann and Dreybrodt (1985a,b) can be used to predict reliable rates from the composition of CaHCO3- solutions with low ionic strength in many geologically relevant situations. Copyright (C) 1997 Elsevier Science Ltd

Effects of microbes and their carbonic anhydrase on Ca2 and Mg2 migration in column-built leached soil-limestone karst systems, 2005, Li W. , Yu L. J. , He Q. F. , Wu Y. , Yuan D. X. , Cao J. H. ,
In natural karst systems, limestone diagenesis can be significantly influenced by bacterial activity in the soil horizon. Here, we investigate the effects of microorganisms on the elements migration of calcium and magnesium in karst soil systems by using different microbial treatments in simulated soil-limestone systems. Two bacterial strains, GLRT102Ca and JFSRT303 were specially studied. The leaching and release of Ca2 in the experiments was characterized by a rapid initial increase followed by a sharp decrease before a gradual approach to equilibrium. In contrast, the Mg2 concentrations in the leachates showed an initial decrease before a gradual approach to equilibrium. Microorganisms significantly promoted Ca2 and Mg2 migration in the simulated systems. The total amounts of Ca2 and Mg2 in leachates varied with microbial treatments. The soil GLRT102Ca columns showed the highest total amount of Ca2 in leachates. This increased by a factor of 2.2 relative to the control columns. The highest total amount of Mg2 in leachates was presented in the soil JFSRT303 columns, which leached 58.0% more total amounts of Mg2 than the control columns. The activities of a microbial specific enzyme, carbonic anhydrase (CA), present in the investigated columns were also examined. Varying levels of CA activities were detected in the leachates collected from soil columns with microbial activity. This suggests that the microbes in soil columns produced and released CA. The mean activity of CA in leachates was significantly correlated with total amount of Ca2 in leachates (r = 0.86, P < 0.01). This implied that microbially produced CA might be a major factor influencing Ca2 release and leaching in natural karst systems. (C) 2005 Elsevier B.V All rights reserved

The cave environment inf luencing the lipid prof ile and hepatic lipogenesis of the f ish Ancistrus cryptophthalmus Reis, 1987 (Siluriformes: Loricariidae), 2013, Bastos V. A. A. , Lopes Ferreira R. , Carvalho D. C. , Pugedo M. L. , De Matos Alves Pinto L.

The metabolism of hypogean organisms is frequently molded by the cave environment traits, especially food scarcity. The aim of the present work was to evaluate the inf luence of such environment on lipid composition and hepatic lipogenesis in the f ish Ancistrus cryptophthalmus. For this, the species was compared to an epigean population of the species. A greater accumulation of total lipids was observed in the cave-dwelling f ish (18.36 g/100 g tissue) compared to the surface f ish (14.09 g/100 g tissue). The muscle fatty acid prof ile also varied between the populations. Arachidonic acid was only detected in the epigean f ish, while docosahexaenoic acid was present in the cave f ish. In the lipid prof ile of Ancistrus cryptophthalmus there was a higher proportion of saturated fatty acids, followed by monounsaturated and polyunsaturated fatty acids; Ancistrus sp. showed a predominance of monounsaturated fatty acids. Signif icant differences were also observed in the activities of the hepatic enzymes glucose-6-phosphate dehydrogenase and malic enzyme. The activities of these two enzymes were greater in the epigean animals. The differences could be related to different food availability observed in the two environments. An ecotone zone was observed, located next to the entrance of the Lapa do Angélica cave (Goiás State, Brazil), where the f ishes showed characteristics that were intermediate between those of hypogean f ishes from deeper within the cave, and the epigean population. It could be concluded that the characteristics of the cave environment signif icantly inf luenced the composition of muscle fatty acids and lipogenesis in the hypogean f ish Ancistrus cryptophthalmus.

Diversity and biosynthetic potential of culturable aerobic heterotrophic bacteria isolated from Magura Cave, Bulgaria, 2013, Tomova I. , Lazarkevich I. , Tomova A. , Kambourova M. , Vasilevatonkova E.

Biocapacity of bacteria inhabiting karstic caves to produce valuable biologically active compounds is still slightly investigated. A total of 46 culturable heterotrophic bacteria were isolated under aerobic conditions from the Gallery with pre-historical drawings in Magura Cave, Bulgaria. Phylogenetic analysis revealed that most of bacterial isolates aff iliated with Proteobacteria (63%), followed by Actinobacteria (10.9%), Bacteroidetes (10.9%), and Firmicutes (6.5%). A strong domination of Gram-negative bacteria (total 81%) belonging to nine genera: Serratia, Pseudomonas, Enterobacter, Sphingobacterium, Stenotrophomonas, Commamonas, Acinetobacter, Obesumbacterium, and Myroides, was observed. Gram-positive isolates were represented by the genera Bacillus, Arthrobacter, and Micrococcus. One isolate showed a signif icant phylogenetic distance to the closest neighbor and could represent novel species. Heterotrophic bacterial isolates from Magura Cave were investigated for hydrolytic enzymes production, antimicrobial and hemolytic activity. Predominance of producers of protease (87%), followed by xanthan lyase (64%), lipase (40%), β-glycosidase (40%), and phytase (21%) was observed. Over 75% of the isolates demonstrated antimicrobial and hemolytic activity. The results suggest that heterotrophic bacteria isolated from Magura Cave could be a valuable source of industrially relevant psychrotolerant enzymes and bioactive metabolites. This study is a f irst report on the taxonomic composition and biological activity of culturable bacteria inhabiting a cave in Bulgaria.

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