The role of Ala231 and Trp227 in the substrate specificities of fungal 17β-hydroxysteroid dehydrogenase and trihydroxynaphthalene reductase: Steroids versus smaller substrates

Structure of a short-chain dehydrogenase/reductase fromBacillus anthracis

“…The binding motif for NADP is well conserved in the SDR superfamily and the binding mode seen here is very similar to that observed in other family members (Kallberg et al, 2002;Zhang et al, 2009;Svegelj et al, 2011;Price et al, 2004;Yamashita et al, 2003;Yamazawa et al, 2011). The binding pocket for the adenine ring is mainly formed by residues from the N-terminal part of the protein, while the binding of the nicotinamide moiety involves the catalytic tetrad and the C-terminal part of the protein.…”

“…More than 300 SDR families have been identified, among which about 50% are found only in bacteria (Kallberg et al, 2010). Substrates for SDRs include many important metabolites such as sugars and their derivatives in carbohydrate metabolism (Koropatkin & Holden, 2005;Zhang et al, 2009), steroids in signal transduction (Benach et al, 2002;Svegelj et al, 2011) and keto-acyl-(acyl carrier proteins) and enoyl-acyl-(acyl carrier proteins) in fatty-acid synthesis (Lee et al, 2007;Kim et al, 2010;Price et al, 2004;Zaccai et al, 2008). SDRs usually consist of two domains: a coenzyme-binding domain and a substrate-binding domain.…”

Engineering Mycobacterium smegmatis for testosterone production

“…As the genes encoding 17β‐HSD enzymes from mycobacterial species have not been identified and these proteins have been only partially purified and characterized (Goren et al ., 1983; Egorova et al ., 2002a, 2005), we initially selected as enzyme candidates for metabolic engineering the well‐described 17β‐HSDs from the bacterium C. testosteroni (Schultz et al ., 1977; Lefebvre et al .,1979; Minard et al ., 1985 ; Genti‐Raimondi et al ., 1991; Yin et al ., 1991; Abalain et al ., 1993; Benach et al ., 1996, 2002; Oppermann et al ., 1997; Cabrera et al ., 2000) and the fungus C. lunatus (Plemenitas et al ., 1988; Rižner et al ., 1996, 1999, 2000, 2001a,b; Rižner and Zakelj‐Mavric, 2000; Zorko et al ., 2000; Kristan et al ., 2003, 2005, 2007a,b; Cassetta et al ., 2005; Ulrih and Lanisnik Rižner, 2006; Brunskole et al ., 2009; Svegelj et al ., 2012), because both enzymes present some relevant differences. Although they catalyse a reversible reaction and display similar reaction mechanisms, the reaction equilibrium of the fungal 17β‐HSD is shifted towards reduction, whereas the bacterial enzyme is shifted towards oxidation, as this enzyme is mainly involved into the TS catabolism in C. testosteroni (Genti‐Raimondi et al., 1990; Cabrera et al ., 2000).…”

“…To overcome the first of these factors, works to identify non‐reversible 17β‐HSDs and/or to modify the characterized enzymes by protein engineering can be explored. Several in vitro attempts have been already done to design rationally 17β‐HSD mutants from C. testosteroni and C. lunatus which present alterations in substrate specificity and/or coenzyme requirements, as well as improvements overall catalytic activity (Oppermann et al ., 1997; Kristan et al ., 2003, 2005, 2007a,b; Brunskole et al ., 2009; Svegelj et al ., 2012). To overcome the second factor, the control of bacterial metabolism by metabolic engineering and systems biology approaches would be useful.…”

Substrate scope of a dehydrogenase from Sphingomonas species A1 and its potential application in the synthesis of rare sugars and sugar derivatives

“…While the cofactor-binding domain is usually conserved, the substrate-binding domain varies and determines the substrate specificity (Kavanagh et al, 2008). SDR family enzymes use NADP(H) or NAD(H) as a cofactor and substrates include important metabolites such as sugars and their derivatives in carbohydrate metabolism (Koropatkin and Holden, 2005;Zhang et al, 2009), steroids in signal transduction (Benach et al, 2002;Svegelj et al, 2012), and keto-acyl-(acyl carrier proteins) and enoyl-acyl-(acyl carrier proteins) in fatty-acid synthesis (Kim et al, 2011;Blaise et al, 2017). More than 170 000 enzymes in the SDR family are registered in UniProtKB (January 2018).…”