Functions Of Terpenoids Research Articles

Microbial-type terpene synthase genes occur widely in nonseed land plants, but not in seed plants

The vast abundance of terpene natural products in nature is due to enzymes known as terpene synthases (TPSs) that convert acyclic prenyl diphosphate precursors into a multitude of cyclic and acyclic carbon skeletons. Yet the evolution of TPSs is not well understood at higher levels of classification. Microbial TPSs from bacteria and fungi are only distantly related to typical plant TPSs, whereas genes similar to microbial TPS genes have been recently identified in the lycophyte Selaginella moellendorffii The goal of this study was to investigate the distribution, evolution, and biochemical functions of microbial terpene synthase-like (MTPSL) genes in other plants. By analyzing the transcriptomes of 1,103 plant species ranging from green algae to flowering plants, putative MTPSL genes were identified predominantly from nonseed plants, including liverworts, mosses, hornworts, lycophytes, and monilophytes. Directed searching for MTPSL genes in the sequenced genomes of a wide range of seed plants confirmed their general absence in this group. Among themselves, MTPSL proteins from nonseed plants form four major groups, with two of these more closely related to bacterial TPSs and the other two to fungal TPSs. Two of the four groups contain a canonical aspartate-rich "DDxxD" motif. The third group has a "DDxxxD" motif, and the fourth group has only the first two "DD" conserved in this motif. Upon heterologous expression, representative members from each of the four groups displayed diverse catalytic functions as monoterpene and sesquiterpene synthases, suggesting these are important for terpene formation in nonseed plants.

Quaternary ammonium derivatives of natural terpenoids. Synthesis and properties

In this review, we summarized and analyzed the literature data (from 1963 to March, 2014) on the synthesis and properties of quaternary ammonium derivatives of citronellal, menthol, camphor, lambertian acid, dehydroabietic acid, levopimaric acid, isosteviol, steviol, betulinic acid, dihydrobetulinic acid, platanic acid, oleanolic acid, ursolic acid, and polyprenols. Functionalization of terpenoids with ammnoium groups offers them new properties, such as cholinotropic, antiviral, and antimicrobial activities, or transforms them into chiral ionic liquids having a practical potential for application as chiral phasetransfer catalysts. The synthesis of ammonium derivatives of terpenoids possessing properties of cationic lipids or dimeric bis-quaternary ammonium surfactants was proved to have a promising outlook. A specific attention was paid to the method developed for transformation of any hydrophobic terpenoid or steroid into an amphiphilic water-soluble compound self-organized in the aqueous medium into vesicles (liposomes) forming cell-penetrating complexes with DNA.

Design and characterization of an efficient CYP105A1-based whole-cell biocatalyst for the conversion of resin acid diterpenoids in permeabilized Escherichia coli

Cytochrome P450 enzymes exhibit a tremendous potential for biotechnological applications due to their ability to introduce oxygen into non-activated carbon atoms. Their catalytic diversity is complemented by a broad substrate range covering many natural compounds. Especially the functionalization of terpenoids by P450s becomes increasingly interesting due to the diverse biological effects of these compounds. The bacterial CYP105A1 from Streptomyces griseolus was recently identified to carry out a one-step hydroxylation of several abietane-type resin acids. In this work, a whole-cell system for CYP105A1 with its heterologous electron transfer proteins Arh1 and Etp1(fd) from Schizosaccharomyces pombe was designed in Escherichia coli JM109 cells. Additionally, an enzyme-coupled cofactor regeneration system was integrated by co-expression of alcohol dehydrogenase from Lactobacillus brevis. In order to overcome mass transfer limitations of substrate into the cell, different agents were tested towards their permeabilizing activity on the E. coli membrane. The peptide antibiotic polymyxin B proved to be the most effective permeabilizer. After optimising the expression and conversion conditions, the cells were able to completely convert 200μM of abietic acid into 15-hydroxyabietic acid within 2h, exhibiting an initial conversion rate of 125μM/h. These results demonstrate the high potential of this whole-cell system for the synthesis of functionalized resin acid diterpenoids.

Expression of terpenoid synthase mRNA and terpenoid content in salt stressed mangrove

The halophytic Kandelia candel and Bruguiera gymnorrhiza are ideal model for studying the molecular mechanisms of salinity tolerance in mangrove plants. The correlation between mRNA expression of four oxidosqualene cyclase (OSC) genes namely, KcMS multifunctional terpenoid synthase and KcCAS cyloartenol synthase (K. candel), BgbAS beta-amyrin synthase and BgLUS lupeol synthase (B. gymnorrhiza) and salt concentration was examined. mRNA level of KcMS was increased with salt concentration in both roots and leaves of K. candel. Similarly, salt stress increased the mRNA levels of BgLUS and BgbAS in the root of B. gymnorrhiza. This result suggests that the function of terpenoids in root is associated with the salt stress. In contrast to these observations, the mRNA level of KcCAS was not modulated by salt stress in the roots, and decreased in the leaves. These results therefore suggest that the terpenoids but not phytosterols play an important role to cope with the salt stress in mangrove root. The content and proportion of beta-amyrin and lupeol increased with salinity in the root of K. candel and B. gymnorrhiza, providing additional evidence for the protective role of terpenoids. However, beta-amyrin and lupeol in B. gymnorrhiza leaves decreased with salt concentration, suggesting that the physiological significance for the terpenoids in the leaf may differ from that for the root.

Harrewijn P., van Oosten A.M., Piron P.G.M. Natural terpenoids as messengers. A multidisciplinary study of their production, biological functions and practical applications.

Harrewijn P., van Oosten A.M., Piron P.G.M. Natural terpenoids as messengers. A multidisciplinary study of their production, biological functions and practical applications.

ChemInform Abstract: Ring A Functionalization of Terpenoids by the Unusual Baeyer—Villiger Rearrangement of Aliphatic Aldehydes.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Ring A Functionalization of Terpenoids by the Unusual Baeyer-Villiger Rearrangement of Aliphatic Aldehydes

Ring A Functionalization of Terpenoids by the Unusual Baeyer-Villiger Rearrangement of Aliphatic Aldehydes

Dynamic Analysis of Lipid Membranes

In 1979, G. Ourisson et al. postulated, in the theory of the evolution of biomembranes, that hopanoids, α, ω-dipolar carotenoids and other terpenoids might play the same role in procaryotes as cholesterol plays in eucaryotes, that is, they are membrane reinforcers.Using UV-VIS spectrometries, we at first verified that α, ω-dipolar carotenoids are incorporated into the phospholipid bilayers in a transmembrane manner. Then, we established well ordered bilayer systems with phospholipid/cholesterol/photosensitive probe, in which we directly proved, using a photochemical method, the perpendicular orientation of cholesterol to the membrane plane with its chain terminal buried in the middle of the bilayer.The function of terpenoids as membrane reinforcers was also verified by developing a stopped-flow/light scattering method upon an osmotic shock in unilamellar vesicles to evaluate the water permeability and a solid-state 2H-NMR technique on oriented multibilayers to characterize the dynamics of the lipid chains and the orientation of the incorporated terpenoids in the membrane.