CYP264B1 from Sorangium cellulosum So ce56: a fascinating norisoprenoid and sesquiterpene hydroxylase

Abstract

Many terpenes and terpenoid compounds are known as bioactive substances with desirable fragrance and medicinal activities. Modification of such compounds to yield new derivatives with desired properties is particularly attractive. Cytochrome P450 monooxygenases are potential enzymes for these reactions due to their capability of performing different reactions on a variety of substrates. We report here the characterization of CYP264B1 from Sorangium cellulosum So ce56 as a novel sesquiterpene hydroxylase. CYP264B1 was able to convert various sesquiterpenes including nootkatone and norisoprenoids (α-ionone and β-ionone). Nootkatone, an important grapefruit aromatic sesquiterpenoid, was hydroxylated mainly at position C-13. The product has been shown to have the highest antiproliferative activity compared with other nootkatone derivatives. In addition, CYP264B1 was found to hydroxylate α- and β-ionone, important aroma compounds of floral scents, regioselectively at position C-3. The products, 3-hydroxy-β-ionone and 13-hydroxy-nootkatone, were confirmed by (1)H and (13)C NMR. The kinetics of the product formation was analyzed by high-performance liquid chromatography, and the K ( m ) and k (cat) values were calculated. The results of docking α-/β-ionone and nootkatone into a homology model of CYP264B1 revealed insights into the structural basis of these selective hydroxylations.

Conversions of Tricyclic Antidepressants and Antipsychotics with Selected P450s fromSorangium cellulosumSo ce56

“…Therefore, we investigated 10 P450s from S. cellulosum-a bacterium typically found in soil (Shimkets et al, 2006), where it is exposed to a variety of xenobiotics-for their ability to convert tricyclic drugs. Terpenes and terpenoids as well as fatty acids have already been identified as substrates for these wild-type P450s in previous studies (Khatri et al, 2010a(Khatri et al, ,b, 2014Ly et al, 2012;Schifrin et al, 2014). Moreover, 4-methyl-3-phenyl-coumarin, a tricyclic molecule, was identified as a substrate for CYP264A1 .…”

“…For the past few years, we have been engaged in the study of novel P450s from myxobacteria, and some P450s from S. cellulosum So ce56 have shown a potential for industrial and biotechnological applications (Khatri et al, 2010a(Khatri et al, ,b, 2013(Khatri et al, , 2014Ly et al, 2012;Ringle et al, 2013). We were also able to develop an efficient E. coli-based whole-cell bioconversion system for some myxobacterial P450s .…”

“…Comparing imipramine and clomipramine, there is no significant difference between their conversions, suggesting that the halogen dmd.aspetjournals.org group at the aromatic ring does not seem to play a notable role in the reaction. Unexpectedly, the homolog of this enzyme from the same strain, CYP264B1, which shows no activity toward the tested tricyclic compounds (see Table 2), acts as a norisoprenoid and sesquiterpene hydroxylase (Ly et al, 2012).…”

“…In 2007, the myxobacterium Sorangium cellulosum So ce56 was sequenced and 21 P450 genes were identified (Schneiker et al, 2007;Khatri et al, 2010b). Although, the physiologic roles of those P450s are still not known, some of them are able to convert exogenous substrates such as terpenes and terpenoids or fatty acids (Khatri et al, 2010b;Ly et al, 2012). However, the potential for the conversion of pharmaceutically interesting compounds has not yet been tested.…”

Characterization of the Gene Cluster CYP264B1‐geoA from Sorangium cellulosum So ce56: Biosynthesis of (+)‐Eremophilene and Its Hydroxylation

“…CYP264B1 is one of 21 cytochrome P450s in S. cellulosum So ce56, [53,54] and has previously been shown to catalyze selective hydroxylation of (+)-nootkatone (1 b) and the norisoprenoids a-and b-ionone; however, smaller monoterpenes and bigger diterpenes and steroids were not able to bind. [55] geoA is one of three putative TS genes in S. cellulosum So ce56. [5] The in vitro enzymatic activity of geoA was examined, and E. coli whole-cell systems for the production of higher yields of the geoA and CYP264B1 products were developed.…”