The use of whole‐cell biocatalysts enables catalyst application in microaqueous reaction systems, in which the liquid phase consists of high substrate loadings in organic solvents, to enable access to high concentrations of easy‐to‐purify product. One current research focus is the modularization of single reaction steps to (i) enable flexible combinations into multi‐step enzyme reactions, (ii) investigate ideal reaction conditions, and (iii) facilitate catalyst handling and recycling. Therefore, we published the easy‐to‐apply encapsulation of a lyophilized whole‐cell catalyst in a polymeric membrane recently. These catalytic “teabags” were demonstrated to enable flexible catalyst combinations for multi‐step reactions and excellent recyclability during repeated batch experiments. We now describe the applicability of these “teabags” on a larger scale by using the new SpinChem reactor and a classical stirred‐tank reactor model. As an alternative, we investigate the described alginate entrapment approach and compare the results. The carboligation reaction towards (R)‐benzoin, using lyophilized E. coli that enclose Pseudomonas fluorescens benzaldehyde lyase (EC 4.1.2.38), served as a model reaction. It was demonstrated that the catalytic “teabags” are scalable and perform equally on the investigatory 5 mL scale and the preparative 140 mL reactor scale. Tested in a more advanced application, the “teabags” were proven to be useful in a one‐pot two‐step reaction for the gram‐scale production of 1‐phenylpropane‐1,2‐diol by using the SpinChem reactor, which allowed to reach an industrially relevant product concentration (32.9 g L−1) and space–time yield (8.2 g L−1 d−1).

Phenylobacterium immobile strain E is a soil bacterium with a striking metabolism relying on xenobiotics, such as the herbicide pyrazon, as sole carbon source instead of more bioavailable molecules. Pyrazon is a heterocyclic aromatic compound of environmental concern and its biodegradation pathway has only been reported in P. immobile. The multicomponent pyrazon oxygenase (PPO), a Rieske non-heme iron oxygenase, incorporates molecular oxygen at the 2,3 position of the pyrazon phenyl moiety as first step of degradation, generating a cis-dihydrodiendiol. The aim of this work was to identify the genes encoding for each one of the PPO components and enable their functional assembly in Escherichia coli. P. immobile strain E genome sequencing revealed genes encoding for RO components, such as ferredoxin-, reductase-, α- and β-subunits of an oxygenase. Though, P. immobile E displays three prominent differences with respect to the ROs currently characterized: (1) an operon-like organization for PPO is absent, (2) all the elements are randomly scattered in its DNA, (3) not only one, but 19 different α-subunits are encoded in its genome. Herein, we report the identification of the PPO components involved in pyrazon cis-dihydroxylation in P. immobile, its appropriate assembly, and its functional reconstitution in E. coli. Our results contributes with the essential missing pieces to complete the overall elucidation of the PPO from P. immobile. Key points • Phenylobacterium immobile E DSM 1986 harbors the only described pyrazon oxygenase (PPO). • We elucidated the genes encoding for all PPO components. • Heterologous expression of PPO enabled pyrazon dihydroxylation in E. coli JW5510.

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