Enzymes in Soils
Soil enzymes. Enzymes in any of the states of occurrence in soils (Ladd et al., 1996).
Numerous processes in soil depend on enzymatic catalysis, including organic matter decomposition, gas emission and sink, pollutants breakdown, energy flow, and nutrient cycling in ecosystem.
Enzymes in soils are associated with different soil constituents. Intracellular enzymes are present in proliferating microorganisms (primarily bacteria and fungi), plant roots, and soil microfauna, or attached to dead cells and cell debris. Numerous extracellular enzymes usually operate at a distance from the parent cell; the capacity to produce and secrete biocatalysts is of survival importance for soil microorganisms and plants. Enzymes in the liquid phase (extracellular as well as released from lysed cells) have generally a short half-life due to rapid denaturation and degradation. However, when complexed with clay minerals or humic colloids, enzymes retain their catalytic properties