Roles of Urease in Plant Cells

Polacco, Joseph C.; Holland, Mark

doi:10.1016/s0074-7696(08)60425-8

Cited by 130 publications

(122 citation statements)

References 139 publications

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“…Therefore, the cloned A. thaliana ␦-OAT cDNA does not seem to encode an isoenzyme localized in a distinct subcellular compartment. This is in agreement with the subcellular localization of the plant ␦-OAT by measurement of its activity in isolated mitochondria (Taylor and Stewart, 1981;Polacco and Holland, 1993) and with the fact that arginase, the other enzyme of Arg catabolism, is also localized in this organelle (Taylor and Stewart, 1981).…”

Section: Discussionsupporting

confidence: 87%

“…Urea appears to have a function in recycling nitrogen into ammonium via urease (Zonia et al, 1995). The massively de novo synthesized Orn is transformed into glutamate semialdehyde via the ␦-OAT enzyme, but this does not appear to influence the Pro levels (Polacco and Holland, 1993). In fact, glutamate semialdehyde seems to be oxidized into glutamate via P5C dehydrogenase which can then be used for transamination or to generate new carbon constituents upon entry into the Krebs cycle as a ketoglutarate (Polacco and Holland, 1993).…”

Section: Discussionmentioning

confidence: 99%

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Isolation of the Ornithine-δ-Aminotransferase cDNA and Effect of Salt Stress on Its Expression inArabidopsis thaliana1

et al. 1998

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To evaluate the relative importance of ornithine (Orn) as a precursor in proline (Pro) synthesis, we isolated and sequenced a cDNA encoding the Orn-␦-aminotransferase (␦-OAT) from Arabidopsis thaliana. The deduced amino acid sequence showed high homology with bacterial, yeast, mammalian, and plant sequences, and the N-terminal residues exhibited several common features with a mitochondrial transit peptide. Our results show that under both salt stress and normal conditions, ␦-OAT activity and mRNA in young plantlets are slightly higher than in older plants. This appears to be related to the necessity to dispose of an easy recycling product, glutamate. Analysis of the expression of the gene revealed a close association with salt stress and Pro production. In young plantlets, free Pro content, ⌬ 1 -pyrroline-5-carboxylate synthase mRNA, ␦-OAT activity, and ␦-OAT mRNA were all increased by salt-stress treatment. These results suggest that for A. thaliana, the Orn pathway, together with the glutamate pathway, plays an important role in Pro accumulation during osmotic stress. Conversely, in 4-week-old A. thaliana plants, although free Pro level also increased under salt-stress conditions, the ␦-OAT activity appeared to be unchanged and ␦-OAT mRNA was not detectable. ⌬ 1 -pyrroline-5-carboxylate synthase mRNA was still induced at a similar level. Therefore, for the adult plants the free Pro increase seemed to be due to the activity of the enzymes of the glutamate pathway.

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Section: Discussionsupporting

confidence: 87%

Section: Discussionmentioning

confidence: 99%

Isolation of the Ornithine-δ-Aminotransferase cDNA and Effect of Salt Stress on Its Expression inArabidopsis thaliana1

et al. 1998

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“…This observation contrasts with the results obtained in pea ovaries in which arginase and ODC activities are absent (Pérez-Amador and Carbonell, 1995). The characteristics of arginase from tomato ovaries ( K , value, effect of Mn2+ ions, and a high pH optimum) agree with those found in arginases from other sources, including plants and animals (Wright et al, 1981;Kang and Cho, 1990;Polacco and Holland, 1993;Carvajal et al, 1996). A relative high arginase activity is present in unpollinated ovaries up to 12 d p.a., supporting the idea that Arg is actively metabolized in ovaries.…”

Section: Arginase Adc and O D C In Unpollinated Ovaries And Young Fmentioning

confidence: 60%

Arginase, Arginine Decarboxylase, Ornithine Decarboxylase, and Polyamines in Tomato Ovaries (Changes in Unpollinated Ovaries and Parthenocarpic Fruits Induced by Auxin or Gibberellin)

et al. 1996

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Arginase (EC 3.5.3.1) activity has been found in the ovaries and young fruits of tomato (Lycopersicon esculentum Mill. cv Rutgers). Changes in arginase, arginine decarboxylase (EC 4.1.1.1 9), and ornithine decarboxylase activity (EC 4.1 .I .17) and levels of free and conjugated putrescine, spermidine, and spermine were determined in unpollinated ovaries and in parthenocarpic fruits during the early stages of development induced by 2,4-dichlorophenoxyacetic acid (2,4-D) or gibberellic acid (CA,). Levels of arginase, free spermine, and conjugates of the three polyamines were constant in unpollinated ovaries and characteristic of a presenescent step. A marked decrease in arginase activity, free spermine, and polyamine conjugates was associated with the initiation of fruit growth due to cell division, and when cell expansion was initiated, the absence of arginase indicated a redirection of nitrogen metabolism to the synthesis of arginine. A transient increase in arginine decarboxylase and ornithine decarboxylase was also observed in 2,4-D-induced fruits. In general, 2,4-D treatments produced faster changes than CA,, and without treatment, unpollinated ovaries developed only slightly and senescence was hardly visible. Sensitivity to 2,4-D and CA, treatment remained for at least 2 weeks postanthesis.

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“…The amount of ammonia can also be monitored spectrophotometrically using a couple system with NADH-dependent glutamate dehydrogenase (ammonia is a substrate for this enzyme). The other product of the reaction, carbon dioxide, can be trapped and monitored by radiological methods with 14 C-labeled urea as a substrate [69]. All of the methods described above are distinct in their sensitivities, ease of use, and susceptibility to interference.…”

Section: Methods For Evaluating Urease Activitymentioning

confidence: 99%

“…Several families of common plants are very rich in urease, including some varieties of beans, melons and squash, and the pine family [13]. Seed urease has been purified to homogeneity from several leguminous plants [14], while leaf urease has also been subjected to investigations [15]. Extraction of urease enzyme from most urease containing plant species is simple and the enzyme is readily available from laboratory suppliers also.…”

Section: Introductionmentioning

confidence: 99%

Effective Use of Plant-Derived Urease in the Field of Geoenvironmental/ Geotechnical Engineering

Ran¹,

Kawasaki²

2016

J Civil Environ Eng

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Geotechnical and geo-environmental engineering applications currently being explored through bio mineralization process include cementation of sands to improve mechanical properties and hence, to enhance bearing capacity and liquefaction resistance, sequestration of carbon, soil erosion control via surficial stabilization, groundwater flow control and remediation of soil and groundwater impacted by metals and radionuclides. Bio mediated system broadly refers to a chemical reaction series that are managed and controlled through biological activities and byproducts resulting from those reactions alter the properties of material in the system. Bio mediated methods such as microbial induced calcite precipitation (MICP), biofilm formation, biogas generation and biopolymers have been developed by injecting or stimulating microbes. MICP is the most widely explored method. Microbes having urease activity enhance the hydrolysis of urea and it helps to control the pH and to precipitate carbonate. Although it is a widely explored bio mediated method it has some disadvantages.The plant-derived urease may offer many benefits over microbial urease to induce carbonate cementation. Therefore, it is advantageous to explore the knowledge regarding such a technique as an eco-friendly method for different applications in the fields of geoenvironmental/geotechnical Engineering. The main objective of this paper is to provide an overview of the importance of plant-derived urease for different applications in the fields of geoenvironmental/ geotechnical engineering. The information presented in this paper may be important for biotechnologists/geoengineers to have wide ranging updates on the current situation.

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Roles of Urease in Plant Cells

Cited by 130 publications

References 139 publications

Isolation of the Ornithine-δ-Aminotransferase cDNA and Effect of Salt Stress on Its Expression inArabidopsis thaliana1

Isolation of the Ornithine-δ-Aminotransferase cDNA and Effect of Salt Stress on Its Expression inArabidopsis thaliana1

Arginase, Arginine Decarboxylase, Ornithine Decarboxylase, and Polyamines in Tomato Ovaries (Changes in Unpollinated Ovaries and Parthenocarpic Fruits Induced by Auxin or Gibberellin)

Effective Use of Plant-Derived Urease in the Field of Geoenvironmental/ Geotechnical Engineering

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