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Factors Responsible for Spatial Distribution of in Soil
Published in Suhaib A. Bandh, Javid A. Parray, Nowsheen Shameem, Climate Change and Microbial Diversity, 2023
Phosphorus is an essential element of life. It is the element of genetic information, cellular structure as well as of energy transport. The main source of phosphorus in soil is from weathering of rocks. The living organisms could assimilate only dissolved phosphate, an enzyme named phosphatase plays the most important role in transforming phosphate from soil organic matter into soluble form (Caldwell, 2005). The main sources of phosphatase enzyme are bacteria, fungi, and plant roots. Phosphatase enzyme cleaves phosphate from its substrate, transforming complex form into assimilated form. Thus, phosphatase enzyme synthesis is regulated by the availability of phosphate in soil in combination with its demand by living organisms. The rhizosphere region of soil which consists of both plant roots and mycorrhiza as well as root associated or free-living microorganisms secrete phosphatase enzyme in the soil. Therefore, in this zone, the soil contains both intracellular as well as extracellular phosphatase enzyme with very high concentration. Furthermore, the phosphatase enzyme gets stabilized on clay and iron or aluminum oxides as surface-reactive particles. Continuously through natural weathering, inorganic phosphate gets transformed into organic phosphate. After complete transformation, about 90% of phosphate in the soil comprised of organic phosphate which includes microbial phosphate in majority (Turner, 2013). Thus, in these weathered soil, phosphatase activity plays the most crucial role by cycling phosphate from soil organic matter to plant availability.
Soil Enzymes – a Tool to Monitor Soil-forming Processes in Coal Mine Spoil Heaps
Published in Artur Dyczko, Andrzej M. Jagodziński, Gabriela Woźniak, Green Scenarios: Mining Industry Responses to Environmental Challenges of the Anthropocene Epoch, 2022
The term “phosphatase” is used to refer to a wide range of enzymes that catalyses the hydrolysis of esters of orthophosphoric acid (Condron et al. 2005). Phosphatases are enzymes that play an important role in soil as they stimulate the transformation of organic phosphorus compounds into inorganic phosphates (HPO42- and H2PO4-), which are directly available to plants and soil organisms (Bielińska 2005). Lack of phosphorus in soil stimulates plant roots and microorganisms to increase the secretion of phosphatase to intensify the solubilization and remobilization of phosphate, thereby influencing the ability of the plant to cope with phosphorus-stressed conditions (Kai et al. 2002). The division of phosphatases is based on the number of ester bonds of the respective substrates and they can be divided into: hydralases of phosphate monoesters (phosphomonoesterases), hydralases of phosphate diesters (phosphodiesterases) and hydralases of phosphate triesters (phosphotriesterases) (Margesin & Schinner 1994; Makoi & Ndakidemi 2008). In the soil environment, the following most frequently occur: phosphomonoesterases (e.g. phytases, glycerophosphatases, nucleases), phosphodiesterases, phosphotriesterases, polyphosphatases (e.g. ATP-ases, pyrophosphatases) and P-N hydrolyses (e.g. phosphatidases; Bielińska 2005).
Anatomy, physiology and disease
Published in C M Langton, C F Njeh, The Physical Measurement of Bone, 2016
Matrix vesicles formed from bone cells were once thought to be the controlling determinants of crystallization during modelling and remodelling [57]. These extracellular vesicles, which are pinched away from osteoblasts, contain enzymes such as alkaline phosphatase which are essential for proper mineralization, and other proteins such as bone sialoprotein, which appears very early in the course of osteoblast mineralization in vitro. Indeed, deficiencies in alkaline phosphatase expression result in syndromes of osteomalacia, or ‘soft bone’, characterized by large amounts of osteoid that is not mineralized. However, it is now apparent, notwithstanding the phenotype of deficient alkaline phosphatase, that matrix vesicles are a function of mineralization only during the earliest phases of bone development, when so-called woven bone is produced. During later stages of postnatal development, the bone tissue containing matrix vesicles is resorbed and new tissue is formed which does not contain these vesicles, but which is appropriately mineralized. Hence, only during a specific developmental time period, or in the case of fracture during the production of woven bone, are the matrix vesicles important in mineralization [58, 59].
Bioaugmentation of endosulfan contaminated soil in artificial bed treatment using selected fungal species
Published in Bioremediation Journal, 2019
Jyoti Bisht, N. S. K. Harsh, L. M. S. Palni, Vasudha Agnihotri, Anuj Kumar
Phosphatases are a broad group of enzymes that are capable of catalyzing hydrolysis of esters and anhydrides of phosphoric acid and play key roles in P cycles of soil system (Dick, Cheng, and Wang 2000). In the present study, endosulfan when applied to soil caused a significant decline in both acid and alkaline phosphatase. In case of endosulfan amended soil that was treated with Trametes hirsuta acid phosphatase activity increased significantly with respect to incubation period. Acid phosphatase activity of soil treated with T. versicolor and a fungal consortium remained at par till 20th day after treatment, but later it increased significantly. Though, in soil treated with Cladosproium cladosporioides and Penicillium frequentans it decreased significantly with the incubation period. Alkaline phosphate activity of endosulfan contaminated soil treated with T. hirsuta, T. versicolor or a fungal consortium was decreased significantly, whereas in soil treated with Cladosporium cladosporioides, alkaline phosphatase activity remained at par upto 20th day but later it increased significantly, and at the end of experiment it reached maximum value. At higher concentration it caused more pronounced effect.
Applicability of API ZYM to capture seasonal and spatial variabilities in lake and river sediments
Published in Environmental Technology, 2019
Drashti Patel, Renee Gismondi, Ali Alsaffar, Sonia M. Tiquia-Arashiro
Lipases, esterases, and phosphatases are groups of enzymes that were synthesized most intensively by the sediment microbial communities. The high activity of lipid- and esterase-hydrolysing enzymes in the sediments might be due to the presence of higher lipid compounds in the sediments. Lipid compounds constitute a minor but important fraction of the total organic matter in aquatic sediments [47]. The main sources of lipids in the water bodies include phytoplanktons, zooplanktons, meiobenthos, macrobenthos, and detritus [48]. Other sources include products associated with microbial activity, inputs of terrestrial material from the watershed region, allochthonous pollutant sources such as unleaded and diesel fuels, used engine oils, and engine exhausts [49,50]. Rigo et al. [51] and Aluyor et al. [52] noted that lipases and esterases are capable of hydrolysing fats and oils. Of particular relevance to sediments are organic compounds such as ketones, sterols, fatty acids, hydroxy acids, n-alkanes, and n-alkanols [53,54]. Among the five groups of enzymes surveyed in this study, phosphatases showed the highest potential level of activity in the sediments. Phosphatase activity is prevalent in aquatic bacteria and is closely related to both the phosphorus and carbon cycles [55]. Extracellular phosphatases play important role in supplying phosphorus to heterotrophic microorganisms and to autotrophic algae [56]. Their activities originate from bacterioplankton but also from phytoplankton and zooplankton [57]. Phosphorus acquisition, especially in phosphorus-limited areas, is dependent on the available enzymes to hydrolyse dissolved organic compounds. It is interesting to see that phosphatases increased during summer, which is linked to the decrease in inorganic phosphates in water. Moreover, algae are also producing phosphatases and their variation can be highly modulated by primary production and the factors (e.g. temperature, inorganic phosphates) enhancing it. There are two forms of phosphatases (alkaline and acid phosphatases). While both forms of phosphatases can hydrolyse all phosphoric esters, the activity of alkaline phosphatase is usually higher than the activity of acid phosphatase [58,59]. Higher activity of alkaline phosphatase was also determined in the present study. The least actively synthesized enzymes in the lake sediments were the glycosyl hydrolases, while it was the aminopeptidases in the river sediments (Figure 3(A)). The activity of these enzymes was either low or non-existent in most sediment samples. The highest glycosyl hydrolase activities were observed from site SC1 (located upstream where the water from Lake Huron drains into Lake St Clair). This site also had the highest bacterial and fungal counts and OM concentration (Table 4).