Erratum to: Identification and Characterization of Four Missense Mutations in Brown midrib12 (Bmr12), the Caffeic acid O-Methyltranferase (COMT) of Sorghum

Determination of the Structure and Catalytic Mechanism of Sorghum bicolor Caffeic Acid O-Methyltransferase and the Structural Impact of Three brown midrib12 Mutations

“…The model is further supported by the observed reduction in the proportion of S-residues in plants in which COMT expression is down-regulated as the result of mutations or transgenic approaches (Chabbert et al, 1994;Atanassova et al, 1995;Van Doorsselaere et al, 1995;Guo et al, 2001;Bout and Vermerris, 2003;Marita et al, 2003;Fu et al, 2011;Jung et al, 2012;Sattler et al, 2012;Jung et al, 2013). In plants with reduced COMT activity, the low conversion of 5-hydroxyconiferaldehyde and 5-hydroxyconiferyl alcohol to the methylated derivatives leads to the incorporation of 5-hydroxyconiferyl alcohol into lignin, resulting in 5-hydroxyguaiacyl subunits in the polymer, as observed in maize bm3 mutants (Lapierre et al, 1988;Marita et al, 2003) and sorghum bmr12 mutants (Palmer et al, 2008).…”

“…The production of cellulosic biofuels from sorghum and switchgrass would translate to a lower environmental impact associated with biofuel production (Vermerris et al, 2007;Propheter and Staggenborg, 2010;Wortmann and Regassa, 2011). Second, several bmr12 mutants with reduced COMT activity have been identified in sorghum (Bout and Vermerris, 2003;Saballos et al, 2008;Sattler et al, 2012). Because of their reduced lignin content and altered lignin subunit composition, they are promising as biomass feedstocks for biofuel production (Vermerris et al, 2007;Saballos et al, 2008;Dien et al, 2009;Sattler et al, 2010Sattler et al, , 2012, but they are also of value to study the catalytic mechanism of COMT in this species.…”

“…Second, several bmr12 mutants with reduced COMT activity have been identified in sorghum (Bout and Vermerris, 2003;Saballos et al, 2008;Sattler et al, 2012). Because of their reduced lignin content and altered lignin subunit composition, they are promising as biomass feedstocks for biofuel production (Vermerris et al, 2007;Saballos et al, 2008;Dien et al, 2009;Sattler et al, 2010Sattler et al, , 2012, but they are also of value to study the catalytic mechanism of COMT in this species. This will enable the elucidation of the main role of this enzyme and can form the basis of future protein engineering approaches to modify cell wall composition.…”

“…This will enable the elucidation of the main role of this enzyme and can form the basis of future protein engineering approaches to modify cell wall composition. Based on the genomic sequence of sorghum (Paterson et al, 2009), it possesses only a single gene encoding a functional S-adenosyl-Lmethionine (SAM)-dependent COMT, making sorghum COMT (SbCOMT) an ideal candidate for the effective manipulation of monolignol biosynthesis (Bout and Vermerris, 2003;Sattler et al, 2012). We present here a range of data elucidated for SbCOMT, including crystal structures and thermodynamic and kinetic data, to gain a mechanistic understanding of this key enzyme and to enable future manipulation of the monolignol biosynthesis and lignin content of sorghum.…”

The Structure and Catalytic Mechanism of Sorghum bicolor Caffeoyl-CoA O-Methyltransferase

“…Moreover, the sorghum genome has been fully sequenced (Paterson et al, 2009), and several brown midrib mutations that favorably affect biomass conversion have been identified (Bout and Vermerris, 2003;Saballos et al, 2009Saballos et al, , 2012Sattler et al, 2009). Additionally, a population of chemically mutagenized sorghum has provided another resource for the identification of mutants with improved bioenergy traits (Xin et al, 2008(Xin et al, , 2009Sattler et al, 2012Sattler et al, , 2014Scully et al, 2016).…”