Cloning and Functional Analysis of a Novel Aldo-Keto Reductase from Aloe arborescens

Morita, Hiroyuki; Mizuuchi, Yuusuke; Abe, Tsuyoshi; Kohno, Toshiyuki; Noguchi, Hiroshi; Abe, Ikuro

doi:10.1248/bpb.30.2262

Cited by 13 publications

(7 citation statements)

References 20 publications

(40 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The A. arborescens OKS, along with HpPKS2, is the only enzyme among unmodified plant‐specific type III PKSs that has been shown to have OKS activity. Because the aloe does not accumulate SEK4 and SEK4b, the aloe OKS has been suggested to be involved in the biosynthesis of anthrones and anthraquinones in the plant and SEK4/SEK4b produced in the absence of additional tailoring enzymes in vitro [26,36]. The A. arborescens OKS preferred malonyl‐CoA as a starter substrate for the production of SEK4 and SEK4b.…”

Section: Discussionmentioning

confidence: 99%

Octaketide‐producing type III polyketide synthase from Hypericum perforatum is expressed in dark glands accumulating hypericins

et al. 2008

View full text Add to dashboard Cite

Hypericins are biologically active constituents of Hypericum perforatum (St John’s wort). It is likely that emodin anthrone, an anthraquinone precursor of hypericins, is biosynthesized via the polyketide pathway by type III polyketide synthase (PKS). A PKS from H. perforatum, HpPKS2, was investigated for its possible involvement in the biosynthesis of hypericins. Phylogenetic tree analysis revealed that HpPKS2 groups with functionally divergent non‐chalcone‐producing plant‐specific type III PKSs, but it is not particularly closely related to any of the currently known type III PKSs. A recombinant HpPKS2 expressed in Escherichia coli resulted in an enzyme of ∼ 43 kDa. The purified enzyme catalysed the condensation of acetyl‐CoA with two to seven malonyl‐CoA to yield tri‐ to octaketide products, including octaketides SEK4 and SEK4b, as well as heptaketide aloesone. Although HpPKS2 was found to have octaketide synthase activity, production of emodin anthrone, a supposed octaketide precursor of hypericins, was not detected. The enzyme also accepted isobutyryl‐CoA, benzoyl‐CoA and hexanoyl‐CoA as starter substrates producing a variety of tri‐ to heptaketide products. In situ RNA hybridization localized the HpPKS2 transcripts in H. perforatum leaf margins, flower petals and stamens, specifically in multicellular dark glands accumulating hypericins. Based on our results, HpPKS2 may have a role in the biosynthesis of hypericins in H. perforatum but some additional factors are possibly required for the production of emodin anthrone in vivo.

show abstract

Section: Discussionmentioning

confidence: 99%

Octaketide‐producing type III polyketide synthase from Hypericum perforatum is expressed in dark glands accumulating hypericins

et al. 2008

View full text Add to dashboard Cite

show abstract

“…Cape Aloe; Liliaceae) (Zahn et al, 2007), Aloe arborescens (syn. Candelabra Aloe; Liliaceae) (Morita et al, 2007) and Aloe perryi baker (syn. Perry's Aloe; Liliaceae) (Eshun and He, 2004), among which Aloe vera is the most widely studied species so far for its clinical effectiveness against a variety of skin disorders including burns and wounds (Chithra et al, 1998b;Vogler and Ernst, 1999;Biswas and Mukherjee, 2003).…”

Section: Introductionmentioning

confidence: 99%

Preliminary evaluation: The effects of Aloe ferox Miller and Aloe arborescens Miller on wound healing

Jia¹,

Zhao

Jia³

2008

Journal of Ethnopharmacology

123

View full text Add to dashboard Cite

“…20) Three loop structures (loops A, B, and C) adjacent to the (/) 8 -barrel are required for RC substrate specificity. 20) In higher plants, several enzymes have been reported to reduce sugar-derived RCs: AKR4C1 (barley), 23) AKR4C7 (maize), 24) AKR4C12 (aloe), 25) AKR4C14 (Indian rice), 26) OsAKR1 (Japonica rice), 27) and AKR4C8 and AKR4C9 (Arabidopsis). 1) All of these belong to the AKR4C subfamily.…”

mentioning

confidence: 99%

Functional Analysis of the AKR4C Subfamily ofArabidopsis thaliana: Model Structures, Substrate Specificity, Acrolein Toxicity, and Responses to Light and [CO₂]

Saito

Shimakawa

Nishi

et al. 2013

Bioscience, Biotechnology, and Biochemistry

View full text Add to dashboard Cite

In Arabidopsis thaliana, the aldo-keto reductase (AKR) family includes four enzymes (The AKR4C subfamily: AKR4C8, AKR4C9, AKR4C10, and AKR4C11). AKR4C8 and AKR4C9 might detoxify sugar-derived reactive carbonyls (RCs). We analyzed AKR4C10 and AKR4C11, and compared the enzymatic functions of the four enzymes. Modeling of protein structures based on the known structure of AKR4C9 found an (α/β)8-barrel motif in all four enzymes. Loop structures (A, B, and C) which determine substrate specificity, differed among the four. Both AKR4C10 and AKR4C11 reduced methylglyoxal. AKR4C10 reduced triose phosphates, dihydroxyacetone phosphate (DHAP), and glyceraldehydes 3-phosphate (GAP), the most efficiently of all the AKR4Cs. Acrolein, a lipid-derived RC, inactivated the four enzymes to different degrees. Expression of the AKR4C genes was induced under high-[CO2] and high light, when photosynthesis was enhanced and photosynthates accumulated in the cells. These results suggest that the AKR4C subfamily contributes to the detoxification of sugar-derived RCs in plants.

show abstract

Cloning and Functional Analysis of a Novel Aldo-Keto Reductase from Aloe arborescens

Cited by 13 publications

References 20 publications

Octaketide‐producing type III polyketide synthase from Hypericum perforatum is expressed in dark glands accumulating hypericins

Octaketide‐producing type III polyketide synthase from Hypericum perforatum is expressed in dark glands accumulating hypericins

Preliminary evaluation: The effects of Aloe ferox Miller and Aloe arborescens Miller on wound healing

Functional Analysis of the AKR4C Subfamily ofArabidopsis thaliana: Model Structures, Substrate Specificity, Acrolein Toxicity, and Responses to Light and [CO₂]

Contact Info

Product

Resources

About

Cloning and Functional Analysis of a Novel Aldo-Keto Reductase from Aloe arborescens

Cited by 13 publications

References 20 publications

Octaketide‐producing type III polyketide synthase from Hypericum perforatum is expressed in dark glands accumulating hypericins

Octaketide‐producing type III polyketide synthase from Hypericum perforatum is expressed in dark glands accumulating hypericins

Preliminary evaluation: The effects of Aloe ferox Miller and Aloe arborescens Miller on wound healing

Functional Analysis of the AKR4C Subfamily ofArabidopsis thaliana: Model Structures, Substrate Specificity, Acrolein Toxicity, and Responses to Light and [CO2]

Contact Info

Product

Resources

About

Functional Analysis of the AKR4C Subfamily ofArabidopsis thaliana: Model Structures, Substrate Specificity, Acrolein Toxicity, and Responses to Light and [CO₂]