Cloning and recombinant expression of rat and human kynureninase

Toma, Salvatore; Nakamura, Masayuki; Toné, Shigenobu; Okuno, Etsuo; Kido, Ryo; Breton, Jérôme; Avanzi, Nilla; Cozzi, Liviana; Speciale, C.; Mostardini, Marina; Gatti, Silvia; Benatti, Luca

doi:10.1016/s0014-5793(97)00374-8

Cited by 21 publications

(24 citation statements)

References 21 publications

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“…The importance of PtdSer interaction to robust activation of TAM receptors has been appreciated for almost two decades, and yet a molecular understanding of this effect has not developed (Nakano et al, 1997; Tanabe et al, 1997). Our combined experiment/modeling study here provides a quantitative, mechanistic understanding of TAM signaling, and in doing so provides essential information for specific targeting of TAM signaling during both dysregulation and normal function (Figure 6).…”

Section: Discussionmentioning

confidence: 99%

“…The TAM ligands Gas6 and protein S both bind PtdSer, and many studies have highlighted the importance of this interaction to activation of TAM receptors, though the exact means by which information is transduced from lipid to receptor via ligand is controversial (Dormady et al, 2000; Hall et al, 2002; Hasanbasic et al, 2005; Rajotte et al, 2008; Stenhoff et al, 2004; Yanagita et al, 1999). Earlier work identified PtdSer as an important factor to TAM activation, although it concluded that interaction between the ligand and receptor was entirely dependent upon lipid interaction, which has proven to not be the case (Nakano et al, 1997; Tanabe et al, 1997). More recent work has revisited the influence of PtdSer binding, showing that its effect is not due to a change in receptor-ligand association, and depends strongly on the spectrum of TAM receptors expressed, but has come to somewhat conflicting conclusions regarding which contexts require PtdSer for robust activation (Lew et al, 2014; Tsou et al, 2014).…”

Section: Introductionmentioning

confidence: 99%

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The AXL Receptor Is a Sensor of Ligand Spatial Heterogeneity

2015

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The AXL receptor is a TAM (Tyro3, AXL, MerTK) receptor tyrosine kinase (RTK) important in physiological inflammatory processes such as blood clotting, viral infection, and innate immune-mediated cell clearance. Overexpression of the receptor in a number of solid tumors is increasingly appreciated as a key drug resistance and tumor dissemination mechanism. Although the ligand-receptor (Gas6-AXL) complex structure is known, literature reports on ligand-mediated signaling have provided conflicting conclusions regarding the influence of other factors such as phosphatidylserine binding, and a detailed, mechanistic picture of AXL activation has not emerged. Integrating quantitative experiments with mathematical modeling, we show here that AXL operates to sense local spatial heterogeneity in ligand concentration, a feature consistent with its physiological role in inflammatory cell responses. This effect arises as a result of an intricate reaction-diffusion interaction. Our results demonstrate that AXL functions distinctly from other RTK families, a vital insight for envisioned design of AXL-targeted therapeutic intervention.

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Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

The AXL Receptor Is a Sensor of Ligand Spatial Heterogeneity

2015

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“…Fortunately, mammals have kynureninase that can efficiently hydrolyze 3-HK to alanine and 3-hydroxyanthranilic acid, and the latter can be eventually oxidized to CO 2 and H 2 O or used to synthesize NAD ϩ and NADP ϩ through a quinolinic acid intermediate (16). The mammalian kynureninase is also capable of catalyzing the hydrolysis of kynurenine, but it has a much higher affinity for 3-HK than kynurenine (17), suggesting that the enzyme may play a major role in preventing the accumulation of 3-HK in mammals. Results from our previous study demonstrate that oxidation of tryptophan to 3-HK is also a major pathway for tryptophan catabolism in Aedes aegypti mosquitoes, especially during larval and egg development (18).…”

Section: -Hkmentioning

confidence: 99%

3-Hydroxykynurenine Transaminase Identity with Alanine Glyoxylate Transaminase

Han

Fang

2002

Journal of Biological Chemistry

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This study describes the functional characterization of a specific mosquito transaminase responsible for catalyzing the transamination of 3-hydroxykynurenine (3-HK) to xanthurenic acid (XA). The enzyme was purified from Aedes aegypti larvae by ammonium sulfate fractionation, heat treatment, and various chromatographic techniques, plus non-denaturing electrophoresis. The purified transaminase has a relative molecular mass of 42,500 by SDS-PAGE. N-terminal and internal sequencing of the purified protein and its tryptic fragments resolved a partial N-terminal sequence of 19 amino acid residues and 3 partial internal peptide sequences with 7, 10, and 7 amino acid residues. Using degenerate primers based on the partial internal sequences for PCR amplification and cDNA library screening, a full-length cDNA clone with a 1,167-bp open reading frame was isolated. Its deduced amino acid sequence consists of 389 amino acid residues with a predicted molecular mass of 43,239 and shares 45-46% sequence identity with mammalian alanine glyoxylate transaminases. Northern analysis shows the active transcription of the enzyme in larvae and developing eggs. Substrate specificity analysis of this mosquito transaminase demonstrates that the enzyme is active with 3-HK, kynurenine, or alanine substrates. The enzyme has greater affinity and catalytic efficiency for 3-HK than for kynurenine and alanine. The biochemical characteristics of the enzyme in conjunction with the profiles of 3-HK transaminase activity and XA accumulation during mosquito development clearly point out its physiological function in the 3-HK to XA pathway. Our data suggest that the mosquito transaminase was evolved in a manner precisely reflecting the physiological requirement of detoxifying 3-HK produced in the tryptophan oxidation pathway in the mosquito. 3-HK1 is a natural metabolite in the tryptophan oxidation pathway. However, it is oxidized easily, stimulating the production of reactive oxygen species (1-5). 3-HK concentration is elevated in the brains of patients with AIDS-related dementia (6), Huntington's disease (7,8), and hepatic encephalopathy (9). Recently it has been reported that 3-HK, at low micromolar concentrations, induces apoptosis of neurons prepared from the rat striatum (3, 4, 10). In insects, injection of 3-HK into adult Neobellieria bullata caused instant paralysis, which was followed by death (11). 3-HK also is present in the mammalian lens, where its oxidation product might cross-link lens proteins and contribute to nuclear cataract formation (12-15). To maintain physiological conditions, it apparently is critical for living organisms to be able to tightly regulate the level of 3-HK, thereby preventing overaccumulation of 3-HK.Although 3-HK is toxic to living organisms, the tryptophan to 3-HK pathway is actually the major branch pathway of tryptophan catabolism in mammals. Fortunately, mammals have kynureninase that can efficiently hydrolyze 3-HK to alanine and 3-hydroxyanthranilic acid, and the latter can be eventually oxidized to CO 2 an...

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“…These results suggest that the recombinant T. cruzi kynureninase catabolizes both substrates with similar efficacy. However this recombinant enzyme displays higher K m values when compared to human and rat kynureninases (10-fold higher for 3-hydroxy-Lkynurenine and 2-fold higher for L-kynurenine, for both organisms) (Toma et al, 1997).…”

Section: Kynureninase Activitymentioning

confidence: 75%

“…N-formylkynurenine can also be used as a substrate. Kynureninase has been described in bacteria, fungi, vertebrates (Koushik et al, 1997;Jakoby and Bonner, 1953;Shetty and Gaertner, 1973;Toma et al, 1997;Gaertner and Shetty, 1977;Allegri et al, 2003) and more recently in the only insect known to have a kynureninase gene, the silkworm Bombyx mori (Meng et al, 2009). Two functional orthologs of kynureninase are known.…”

Section: Introductionmentioning

confidence: 99%

Initial characterization of a recombinant kynureninase from Trypanosoma cruzi identified from an EST database

Ecco

Vernal

Razzera³

et al. 2009

Gene

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Kynureninase has been described in bacteria, fungi and animals as an enzyme involved in the catabolic degradation pathway of l-tryptophan. This pyridoxal 5'-phosphate (PLP)-dependent enzyme catalyzes the hydrolytic cleavage of l-kynurenine and 3-hydroxy-l-kynurenine to yield l-alanine and either anthranilic or 3-hydroxyanthranilic acid, respectively. We identified a putative kynureninase gene from a Trypanosoma cruzi project aiming at the structural and functional characterization of more than 100 proteins differentially expressed during metacyclogenesis. This gene encodes a protein similar in size and sequence to kynureninases from other sources. This open reading frame was cloned and the recombinant enzyme was overexpressed. Recombinant T. cruzi kynureninase was purified to homogeneity and its identity was confirmed by mass spectrometry. The apparent molecular mass of the native T. cruzi kynureninase was estimated by gel filtration, suggesting that the protein is a homodimer. Circular dichroism spectrum indicated a mixture of alpha-helix and beta-sheet structure, expected for an aminotransferase fold. l-kynurenine, preferentially hydrolyzed by prokaryotic inducible kynureninases, and 3-hydroxy-l-kynurenine, the preferred substrate in fungi and vertebrates, are both catabolized equally well by T. cruzi kynureninase. Further experimental assays will be performed to fully understand the importance of this enzyme for T. cruzi metabolism.

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Cloning and recombinant expression of rat and human kynureninase

Cited by 21 publications

References 21 publications

The AXL Receptor Is a Sensor of Ligand Spatial Heterogeneity

The AXL Receptor Is a Sensor of Ligand Spatial Heterogeneity

3-Hydroxykynurenine Transaminase Identity with Alanine Glyoxylate Transaminase

Initial characterization of a recombinant kynureninase from Trypanosoma cruzi identified from an EST database

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