Warming alters potential enzyme activity but precipitation regulates chemical transformations in grass litter exposed to simulated climatic changes

2014 ◽  
Vol 75 ◽  
pp. 102-112 ◽  
Author(s):  
Vidya Suseela ◽  
Nishanth Tharayil ◽  
Baoshan Xing ◽  
Jeffrey S. Dukes
Keyword(s):  
Enzyme Activity ◽  
Climatic Changes ◽  
Chemical Transformations ◽  
Grass Litter ◽  
Potential Enzyme Activity

scholarly journals Extracellular Enzyme Activity and Microbial Diversity Measured on Seafloor Exposed Basalts from Loihi Seamount Indicate the Importance of Basalts to Global Biogeochemical Cycling

2014 ◽  
Vol 80 (16) ◽  
pp. 4854-4864 ◽  
Author(s):  
Myrna E. Jacobson Meyers ◽  
Jason B. Sylvan ◽  
Katrina J. Edwards
Keyword(s):  
Enzyme Activity ◽  
Microbial Communities ◽  
Enzyme Activities ◽  
Leucine Aminopeptidase ◽  
Extracellular Enzyme ◽  
Basaltic Rock ◽  
Rrna Gene ◽  
Content Type ◽  
Shelf Sediments ◽  
Potential Enzyme Activity

ABSTRACTSeafloor basalts are widely distributed and host diverse prokaryotic communities, but no data exist concerning the metabolic rates of the resident microbial communities. We present here potential extracellular enzyme activities of leucine aminopeptidase (LAP) and alkaline phosphatase (AP) measured on basalt samples from different locations on Loihi Seamount, HI, coupled with analysis of prokaryotic biomass and pyrosequencing of the bacterial 16S rRNA gene. The community maximum potential enzyme activity (Vmax) of LAP ranged from 0.47 to 0.90 nmol (g rock)−1h−1; theVmaxfor AP was 28 to 60 nmol (g rock)−1h−1. TheKmof LAP ranged from 26 to 33 μM, while theKmfor AP was 2 to 7 μM. Bacterial communities on Loihi basalts were comprised primarily ofAlpha-,Delta-, andGammaproteobacteria,Bacteroidetes, andPlanctomycetes. The putative ability to produce LAP is evenly distributed across the most commonly detected bacterial orders, but the ability to produce AP is likely dominated by bacteria in the ordersXanthomonadales,Flavobacteriales, andPlanctomycetales. The enzyme activities on Loihi basalts were compared to those of other marine environments that have been studied and were found to be similar in magnitude to those from continental shelf sediments and orders of magnitude higher than any measured in the water column, demonstrating that the potential for exposed basalts to transform organic matter is substantial. We propose that microbial communities on basaltic rock play a significant, quantifiable role in benthic biogeochemical processes.

Chemical composition of soil organic matter and potential enzyme activity in the topsoil along a moisture gradient in the High Arctic (Svalbard)

Geoderma ◽  
2020 ◽  
Vol 368 ◽  
pp. 114304 ◽  
Author(s):  
Ekaterina Pushkareva ◽  
Kai-Uwe Eckhardt ◽  
Vivien Hotter ◽  
Aline Frossard ◽  
Peter Leinweber ◽  
...  
Keyword(s):  
Organic Matter ◽  
Enzyme Activity ◽  
Chemical Composition ◽  
Soil Organic Matter ◽  
High Arctic ◽  
Moisture Gradient ◽  
Potential Enzyme Activity

scholarly journals Regional enzyme development in rat brain. Enzymes associated with glucose utilization

1984 ◽  
Vol 218 (1) ◽  
pp. 131-138 ◽  
Author(s):  
S F Leong ◽  
J B Clark
Keyword(s):  
Enzyme Activity ◽  
Lactate Dehydrogenase ◽  
Rat Brain ◽  
Brain Regions ◽  
Glycolytic Enzyme ◽  
Glycolytic Potential ◽  
Key Enzyme ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Potential Enzyme Activity ◽  
The Brain

The development of key enzyme activities concerned with glucose metabolism was studied in six regions of the rat brain in animals from just before birth (-2 days) through the neonatal and suckling period until adulthood (60 days old). The brain regions studied were the cerebellum, medulla oblongata and pons, hypothalamus, striatum, mid-brain and cortex. The enzymes whose developmental patterns were investigated were hexokinase (EC 2.7.1.1), aldolase (EC 4.1.2.13), lactate dehydrogenase (EC 1.1.1.27) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49). Hexokinase, aldolase and lactate dehydrogenase activities develop as a single cluster in all the regions studied, although the timing of this development varies from region to region. Glucose-6-phosphate dehydrogenase activity, however, declines relative to glycolytic enzyme activity as the brain matures. When the different brain regions are compared, it is clear that the medulla develops its glycolytic potential, as indicated by its potential enzyme activity, considerably earlier than the other regions (hypothalamus, striatum and mid-brain), with the cortex and cerebellar activities developing even later. This enzyme developmental sequence correlates well with the neurophylogenetic development of the brain and adds support to the hypothesis that the development of the potential for glycolysis in the brain is a necessary prerequisite for the development of neurological competence.

scholarly journals Potential enzyme activity of thermophilic bacteria from hot spring in Egypt

2020 ◽  
Vol 16 (1) ◽  
pp. 197-206
Author(s):  
Gehad Taha ◽  
Einas El-Shatoury ◽  
Sahar Tolba ◽  
Mohamed Ibrahim
Keyword(s):  
Enzyme Activity ◽  
Hot Spring ◽  
Thermophilic Bacteria ◽  
Potential Enzyme Activity

scholarly journals Disentangling drivers of soil microbial potential enzyme activity across rain regimes: An approach based on the functional trait framework

2020 ◽  
Vol 148 ◽  
pp. 107881 ◽  
Author(s):  
Gabin Piton ◽  
Arnaud Foulquier ◽  
Laura B. Martínez-García ◽  
Nicolas Legay ◽  
Katarina Hedlund ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Functional Trait ◽  
Soil Microbial ◽  
Microbial Potential ◽  
Potential Enzyme Activity

Morphological and biochemical analyses of changes in rat hepatocytes related to wine and ethanol consumption

1984 ◽  
Vol 42 ◽  
pp. 232-233
Author(s):  
S.M. Geyer ◽  
C.L. Mendenhall ◽  
J.T. Hung ◽  
E.L. Cardell ◽  
R.L. Drake ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Enzyme Activity ◽  
Malic Enzyme ◽  
Smooth Endoplasmic Reticulum ◽  
Rat Hepatocytes ◽  
Mature Male ◽  
Treatment Groups ◽  
Malic Enzyme Activity ◽  
Biochemical Analyses

Thirty-three mature male Holtzman rats were randomly placed in 3 treatment groups: Controls (C); Ethanolics (E); and Wine drinkers (W). The animals were fed synthetic diets (Lieber type) with ethanol or wine substituted isocalorically for carbohydrates in the diet of E and W groups, respectively. W received a volume of wine which provided the same gram quantity of alcohol consumed by E. The animals were sacrificed by decapitation after 6 weeks and the livers processed for quantitative triglycerides (T3), proteins, malic enzyme activity (MEA), light microscopy (LM) and electron microscopy (EM). Morphometric analysis of randomly selected LM and EM micrographs was performed to determine organellar changes in centrilobular (CV) and periportal (PV) regions of the liver. This analysis (Table 1) showed that hepatocytes from E were larger than those in C and W groups. Smooth endoplasmic reticulum decreased in E and increased in W compared to C values.

Reductive light activation of enzyme activity

2000 ◽  
Vol 110 (3) ◽  
pp. 295-295
Author(s):  
Louise Anderson ◽  
Per Gardestrom
Keyword(s):  
Enzyme Activity ◽  
Light Activation
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