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They can also use other unnatural aromatic compounds as substrates and play therefore a pivotal role in increasing structural diversity and biological activities of a broad range of natural and unnatural products. In recent years, several prenylated dimeric CDPs have been identified with wide range of bioactivities. In this study, we demonstrate the production of prenylated dimeric CDPs by chemoenzymatic synthesis with a known promiscuous enzyme EchPT1, which uses <jats:italic>cyclo<\/jats:italic>-<jats:sc>l<\/jats:sc>-Trp-<jats:sc>l<\/jats:sc>-Ala as natural substrate for reverse <jats:italic>C2<\/jats:italic>-prenylation. High product yields were achieved with EchPT1 for C3-N1\u2032 and C3-C3\u2032 linked dimers of <jats:italic>cyclo<\/jats:italic>-<jats:sc>l<\/jats:sc>-Trp-<jats:sc>l<\/jats:sc>-Trp. Isolation and structural elucidation confirmed the product structures to be reversely C19\/C19\u2032-mono- and diprenylated <jats:italic>cyclo<\/jats:italic>-<jats:sc>l<\/jats:sc>-Trp-<jats:sc>l<\/jats:sc>-Trp dimers. Our study provides an additional example for increasing structural diversity by prenylation of complex substrates with known biosynthetic enzymes.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Key points<\/jats:title>\n                <jats:p><jats:italic>\u2022 Chemoenzymatic synthesis of prenylated<\/jats:italic>\u00a0<jats:italic>cyclo<\/jats:italic>-<jats:sc>l<\/jats:sc>-Trp-<jats:sc>l<\/jats:sc>-Trp<jats:italic> dimers<\/jats:italic><\/jats:p>\n                <jats:p><jats:italic>\u2022 Same prenylation pattern and position for cyclodipeptides and their dimers<\/jats:italic>.<\/jats:p>\n                <jats:p><jats:italic>\u2022 Indole prenyltransferases such as EchPT1 can be widely used as biocatalysts<\/jats:italic>.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Graphical Abstract<\/jats:title>\n                \n              <\/jats:sec>","DOI":"10.1007\/s00253-023-12773-0","type":"journal-article","created":{"date-parts":[[2023,9,15]],"date-time":"2023-09-15T08:03:47Z","timestamp":1694765027000},"page":"6887-6895","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Prenylation of dimeric cyclo-l-Trp-l-Trp by the promiscuous cyclo-l-Trp-l-Ala prenyltransferase EchPT1"],"prefix":"10.1007","volume":"107","author":[{"given":"Wen","family":"Li","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiulan","family":"Xie","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jing","family":"Liu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huili","family":"Yu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4583-2655","authenticated-orcid":false,"given":"Shu-Ming","family":"Li","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2023,9,15]]},"reference":[{"key":"12773_CR1","doi-asserted-by":"publisher","first-page":"71","DOI":"10.1016\/j.jpha.2015.11.005","volume":"6","author":"M Balouiri","year":"2016","unstructured":"Balouiri M, Sadiki M, Ibnsouda SK (2016) Methods for in vitro evaluating antimicrobial activity: a review. 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