para-Nitrophenol 4-monooxygenase and hydroxyquinol 1,2-dioxygenase catalyze sequential transformation of 4-nitrocatechol in Pseudomonas sp. strain WBC-3

Wei, Min; Zhang, Jun‐Jie; Liu, Hong; Zhou, Ning‐Yi

doi:10.1007/s10532-010-9351-2

Cited by 35 publications

(18 citation statements)

References 18 publications

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“…While PnpA1 (80% identical to PnpA), PnpC, PnpD, PnpE, and PnpF exhibit high degrees of identity with the enzymes involved in PNP degradation from several PNP utilizers (3-6), PnpG has a high level of identity with the BT 1,2-dioxygenase of Pseudomonas sp. strain WBC-3 (37).…”

Section: Resultsmentioning

confidence: 99%

The Gene Cluster for para -Nitrophenol Catabolism Is Responsible for 2-Chloro-4-Nitrophenol Degradation in Burkholderia sp. Strain SJ98

Min

Zhang

Zhou

2014

Appl Environ Microbiol

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showed that all of the pnp genes in the pnpABA1CDEF cluster were located in a single operon, which is significantly different from the genetic organization of all other previously reported PNP degradation gene clusters, in which the structural genes were located in three different operons. All of the Pnp proteins were purified to homogeneity as His-tagged proteins. PnpA, a PNP 4-monooxygenase, was found to be able to catalyze the monooxygenation of 2C4NP to CBQ. PnpB, a 1,4-benzoquinone reductase, has the ability to catalyze the reduction of CBQ to chlorohydroquinone. Moreover, PnpB is also able to enhance PnpA activity in vitro in the conversion of 2C4NP to CBQ. Genetic analyses indicated that pnpA plays an essential role in the degradation of both 2C4NP and PNP by gene knockout and complementation. In addition to being responsible for the lower pathway of PNP catabolism, PnpCD, PnpE, and PnpF were also found to be likely involved in that of 2C4NP catabolism. These results indicated that the catabolism of 2C4NP and that of PNP share the same gene cluster in strain SJ98. These findings fill a gap in our understanding of the microbial degradation of 2C4NP at the molecular and biochemical levels.

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Section: Resultsmentioning

confidence: 99%

The Gene Cluster for para -Nitrophenol Catabolism Is Responsible for 2-Chloro-4-Nitrophenol Degradation in Burkholderia sp. Strain SJ98

Min

Zhang

Zhou

2014

Appl Environ Microbiol

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“…strain A1 (Spain and Gibson 1991), Pseudomonas spp. (Liu et al 2005; Wei et al 2010) usually degrade PNP via formation of ‘hydroquinone’ (HQ) as the ring cleavage substrate. A few studies have indicated conversion of HQ into BT, which is then used as the terminal ring cleavage substrate in the degradation of 4-hydroxybenzoate and p -nitrophenol by Candida parapsilosis CBS604 and Pseudomonas aeruginosa HS-D38 respectively (Figure 1A) (Eppink et al 2000; Zheng et al 2009).…”

Section: Introductionmentioning

confidence: 99%

Branching of the p-nitrophenol (PNP) degradation pathway in burkholderia sp. Strain SJ98: Evidences from genetic characterization of PNP gene cluster

et al. 2012

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Aerobic microbial degradation of p-nitrophenol (PNP) has been classically shown to proceed via ‘Hydroquinone (HQ) pathway’ in Gram-negative bacteria, whereas in Gram-positive PNP degraders it proceed via ‘Benzenetriol (BT) pathway’. These pathways are characterized by the ring cleavage of HQ and BT as terminal aromatic intermediates respectively. Earlier reports on PNP degradation have indicated these pathways to be mutually exclusive. We report involvement of both ‘HQ’ and ‘BT’ ring cleavage pathways in PNP degradation by Burkholderia sp. strain SJ98. Genetic characterization of an ~41 Kb DNA fragment harboring PNP degradation gene cluster cloned and sequenced from strain SJ98 showed presence of multiple orfs including pnpC and pnpD which corresponded to previously characterized ‘benzenetriol-dioxygenase (BtD)’ and ‘maleylacetate reductase (MaR)’ respectively. This gene cluster also showed presence of pnpE1 and pnpE2, which shared strong sequence identity to cognate sub-units of ‘hydroquinone dioxygenase’ (HqD). Heterologous expression and biochemical characterization ascertained the identity of PnpE1 and PnpE2. In in vitro assay reconstituted heterotetrameric complex of PnpE1 and PnpE2 catalyzed transformation of hydroquinone (HQ) into corresponding hydroxymuconic semialdehyde (HMS) in a substrate specific manner. Together, these results clearly establish branching of PNP degradation in strain SJ98. We propose that strain SJ98 presents a useful model system for future studies on evolution of microbial degradation of PNP.

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“…In order to determine gentisate 1,2-dioxygenase activity, the formation of maleylpyruvate was measured at 330 nm (ε 330 = 10.800/M cm) (Feng et al, 1999). The activity of hydroxyquinol 1,2-dioxygenase was measured spectrophotometrically by the formation of maleyla cetate at 243 nm (ε 243 = 44.520/M cm) (Wei et al, 2010). One unit of enzyme activity was defined as the amount of enzyme required to generate 1 µmol of product per minute.…”

Section: Methodsmentioning

confidence: 99%

Enzymes Involved in Naproxen Degradation by Planococcus sp. S5

Wojcieszyńska

Domaradzka

Hupert-Kocurek

2016

Polish Journal of Microbiology

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A b s t r a c tNaproxen is a one of the most popular non-steroidal anti-inflammatory drugs (NSAIDs) entering the environment as a result of high consumption. For this reason, there is an emerging need to recognize mechanisms of its degradation and enzymes engaged in this process. Planococcus sp. S5 is a gram positive strain able to degrade naproxen in monosubstrate culture (27%). However, naproxen is not a sufficient growth substrate for this strain. In the presence of benzoate, 4-hydroxybenzoic acid, 3,4-dihydroxybenzoic acid or vanillic acid as growth substrates, the degradation of 21.5%, 71.71%, 14.75% and 8.16% of naproxen was observed respectively. It was shown that the activity of monooxygenase, hydroxyquinol 1,2-dioxygenase, protocatechuate 3,4-dioxygenase and protocatechuate 4,5-dioxyegnase in strain S5 was induced after growth of the strain with naproxen and 4-hydroxybenzoate. Moreover, in the presence of naproxen activity of gentisate 1,2-dioxygenase, enzyme engaged in 4-hydroxybenzoate metabolism, was completely inhibited. The obtained results suggest that monooxygenase and hydroxyquinol 1,2-dioxygenase are the main enzymes in naproxen degradation by Planococcus sp. S5. 178acid produced by Prunus domestica, Melissa officinalis or Vitis vinifera or vanillic acid identified in Juglans regia or Chenopodium murales (Ghareib et al., 2010;Kakkar and Bais, 2014). The objective of our study is to examine the ability of Planococcus sp. S5 to degrade naproxen in either mono-or disubstrate cultures with plant aromatic compounds as growth substrates. Plano coccus sp. S5 was chosen for this study since it degrades salicylate (Łabużek et al., 2003), which is not only the intermediate of naphthalene degradation and mimetic of naproxen, but also belongs to non-steroidal antiinflammatory drugs. Additionally, the aim of this study is to identify enzymes engaged in naproxen degradation by Planococcus sp. S5 in cometabolic conditions. Experimental Materials and MethodsMedia and culture conditions. Planococcus sp. S5 was routinely cultivated in BBL nutrient broth at 30°C and 130 rpm for 24 hours. Then 6 mg/l naproxen was added to the culture. After 48 hours, cells were harvested by centrifugation (5.000 × g at 4°C for 15 min), washed with fresh sterile medium and used as inoculum. Degradation of naproxen in a monosubstrate, as well as cometabolic systems, was performed in 500 ml Erlenmeyer flasks containing 250 ml of the mineral salts medium (Greń et al., 2010) inoculated with cells to a final optical density of about 1.5 and 0.5 at λ = 600 nm (OD600) for the monosubstrate and cometabolic systems, respectively. For degradation experiments two control cultures were prepared. The uninoculated control (I) consisted of 250 ml of sterile mineral salts medium, while the heatkilled control (II) consisted of 250 ml of autoclaved culture prepared under conditions identical to those of the experimental cultures. Naproxen was added to each flask to obtain a final concentration of 6 mg/l, and all cultures were incubated with shakin...

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para-Nitrophenol 4-monooxygenase and hydroxyquinol 1,2-dioxygenase catalyze sequential transformation of 4-nitrocatechol in Pseudomonas sp. strain WBC-3

Cited by 35 publications

References 18 publications

The Gene Cluster for para -Nitrophenol Catabolism Is Responsible for 2-Chloro-4-Nitrophenol Degradation in Burkholderia sp. Strain SJ98

The Gene Cluster for para -Nitrophenol Catabolism Is Responsible for 2-Chloro-4-Nitrophenol Degradation in Burkholderia sp. Strain SJ98

Branching of the p-nitrophenol (PNP) degradation pathway in burkholderia sp. Strain SJ98: Evidences from genetic characterization of PNP gene cluster

Enzymes Involved in Naproxen Degradation by Planococcus sp. S5

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