The Plant Science Student Conference (PSSC) has been organised by students from the two Leibniz institutes, IPK and IPB, every year for the last 20 years. In this interview, Christina Wäsch (IPK) and Carolin Apel (IPB)…
Over 600 guests came to the IPB on July 4 for the Long Night of Sciences to learn lots of new things and put their knowledge to the test at our science quiz course. This year, our program was aimed equally at children and…
Our 10th Leibniz Plant Biochemistry Symposium on May 7 and 8 was a great success. This year's theme was new methods and research approaches in natural product chemistry. The excellent presentations on active substances and…
Fungal unspecific peroxygenases (UPOs) have gained substantial attention for their versatile oxyfunctionalization chemistry paired with impressive catalytic capabilities. A major drawback, however, remains their sensitivity towards their co‐substrate hydrogen peroxide, necessitating the use of smart in situ hydrogen peroxide generation methods to enable efficient catalysis setups. Herein, we introduce flavin‐containing protein photosensitizers as a new general tool for light‐controlled in situ hydrogen peroxide production. By genetically fusing flavin binding fluorescent proteins and UPOs, we have created two virtually self‐sufficient photo‐enzymes (PhotUPO). Subsequent testing of a versatile substrate panel with the two divergent PhotUPOs revealed two stereoselective conversions. The catalytic performance of the fusion protein was optimized through enzyme and substrate loading variation, enabling up to 24300 turnover numbers (TONs) for the sulfoxidation of methyl phenyl sulfide. The PhotUPO concept was upscaled to a 100 mg substrate preparative scale, enabling the extraction of enantiomerically pure alcohol products.Graphical Abstract
Unspecific peroxygenases (UPOs) have recently gained
attraction as versatile oxyfunctionalization catalysts. One shortcoming,
however, is their susceptibility towards the co-substrate hydrogen
peroxide. As a solution, the concept of light-dependent UPO biocatalysis
with genetically encoded flavin-containing photosensitizer proteins for
in situ hydrogen peroxide production is introduced.
Publications
Bulatović, M. Z.; Maksimović-Ivanić, D.; Bensing, C.; Gómez-Ruiz, S.; Steinborn, D.; Schmidt, H.; Mojić, M.; Korać, A.; Golić, I.; Pérez-Quintanilla, D.; Momčilović, M.; Mijatović, S.; Kaluđerović, G. N.;Organotin(IV)-Loaded Mesoporous Silica as a Biocompatible Strategy in Cancer TreatmentAngew. Chem. Int. Ed.535982-5987(2014)DOI: 10.1002/anie.201400763
The strong therapeutic potential of an organotin(IV) compound loaded in nanostructured silica (SBA‐15pSn) is demonstrated: B16 melanoma tumor growth in syngeneic C57BL/6 mice is almost completely abolished. In contrast to apoptosis as the basic mechanism of the anticancer action of numerous chemotherapeutics, the important advantage of this SBA‐15pSn mesoporous material is the induction of cell differentiation, an effect unknown for metal‐based drugs and nanomaterials alone. This non‐aggressive mode of drug action is highly efficient against cancer cells but is in the concentration range used nontoxic for normal tissue. JNK (Jun‐amino‐terminal kinase)‐independent apoptosis accompanied by the development of the melanocyte‐like nonproliferative phenotype of survived cells indicates the extraordinary potential of SBA‐15pSn to suppress tumor growth without undesirable compensatory proliferation of malignant cells in response to neighboring cell death.