L‐Rhamnulose‐1‐phosphate Aldolase from Thermotoga maritima in Organic Synthesis: One‐Pot Multistep Reactions for the Preparation of Imino‐ and Nitrocyclitols

Abstract

Abstract. Rhamnulose-1-phosphate aldolase from Thermotoga maritima (Rhu1PATm) has been recently cloned and characterized. This hyperthermophilic enzyme offers intriguing possibilities for practical catalysis. This is due to its high stability under extreme reaction conditions, such as high temperature or the presence of organic co-solvents. The Rhu1PATm potentiality in organic synthesis has been explored focusing on i) the reaction stereocontrol, ii) the possibility of combining it with other mesophilic enzymes in multienzyme systems and iii) its application to the synthesis of imino-and nitrocyclitols. In our study, Rhu1PATm diastereoselectivity was similar to the one reported by Rhu1PA from Escherichia coli (Rhu1PAEc). However, we observed significant differences for some aldehyde acceptors. Indeed, the diastereoselectivity control was not complete, since mixtures of L-threo (2R,3S; natural stereopreference) and D-erythro (2R,3R) diastereoisomers were obtained as described for Rhu1PAEc. Rhu1PATm was able to catalyse aldol reactions using nitroaldehydes and N-Cbzaminoaldehydes. Conversion of the selected nitroaldehydes was complete, leading to mixtures of L-threo and D-erythro diastereoisomers, in 95:5 and 75:25 ratios. When N-Cbz-aminoaldehydes were used, aldol reaction yields were lower and the stereoselectivity L-threo:D-erythro ranged between 32:68 to >95:5.

Tuning the Phosphoryl Donor Specificity of Dihydroxyacetone Kinase from ATP to Inorganic Polyphosphate. An Insight from Computational Studies

“…Although several chemical and enzymatic routes of DHAP synthesis have been described in the literature, an efficient method of DHAP preparation is still essential [ 11 ]. In this sense, our research group has developed a straightforward multi-enzyme system for one-pot C–C bond formation catalyzed by DHAP-dependent aldolases, based in the use of the recombinant ATP-dependent DHA kinase from C. freundii CECT 4626, for in situ DHAP formation [ 12 , 13 , 14 , 15 ]. This enzyme has the highest described catalytic efficiency for DHA phosphorylation, about one order of magnitude higher than the rest of the enzymes that have been also used for the preparation of DHAP [ 16 ].…”

Extending Designed Linear Biocatalytic Cascades for Organic Synthesis

“…Biotransformations separated in time are termed “stages”, while one stage may comprise one or more reaction steps. Usually, to overcome reactions incompatibility, some actions have to be taken, like reagents addition at a later point of time, pH adjustment, unreacted substrates removal etc …”

“…Usually, to overcome reactions incompatibility, some actions have to be taken, like reagents addition at a later point of time, pH adjustment, unreacted substrates removal etc. [38]…”

Recent Developments in the Preparation of Carbohydrate Derivatives from Achiral Building Blocks by using Aldolases

“…This catalyst offers outstanding possibilities for industrial applications considering its high stability towards organic solvents even at high temperatures. RhuA1PA Tm has also been successfully integrated in a biocatalytic cascade to produce biologically relevant building blocks from achiral, non‐natural nitroaldehydes and DHA (Scheme a) . The cascade is based on two stereoselective C−C bond formation steps: the first one is catalyzed by the aldolase, whereas the second intramolecular Henry reaction occurs spontaneously.…”