Isofunctional Enzymes PAD1 and UbiX Catalyze Formation of a Novel Cofactor Required by Ferulic Acid Decarboxylase and 4-Hydroxy-3-polyprenylbenzoic Acid Decarboxylase
摘要:
The decarboxylation of antimicrobial aromatic acids such as phenylacrylic acid (cinnamic acid) and ferulic acid by yeast requires two enzymes described as phenylacrylic acid decarboxylase (PAD1) and ferulic acid decarboxylase (FDC). These enzymes are of interest for various biotechnological applications, such as the production of chemical feedstocks from lignin under mild conditions. However, the specific role of each protein in catalyzing the decarboxylation reaction remains unknown. To examine this, we have overexpressed and purified both PAD1 and FDC from E. coli. We demonstrate that PAD1 is a flavin mononucleotide (FMN)-containing protein. However, it does not function as a decarboxylase. Rather, PAD1 catalyzes the formation of a novel, diffusible cofactor required by FDC for decarboxylase activity. Coexpression of FDC and PAD1 results in the production of FDC with high levels cofactor bound. Holo-FDC catalyzes the decarboxylation of phenylacrylic acid, coumaric acid and ferulic acid with apparent kcat ranging from 1.44.6 s(-1). The UV-visible and mass spectra of the cofactor indicate that it appears to be a novel, modified form of reduced FMN; however, its instability precluded determination of its structure. The E. coli enzymes UbiX and UbiD are related by sequence to PAD1 and FDC respectively and are involved in the decarboxylation of 4-hydroxy-3-octaprenylbenzoic acid, an intermediate in ubiquinone biosynthesis. We found that endogenous UbiX can also activate FDC. This implies that the same cofactor is required for decarboxylation of 4-hydroxy-3-polyprenylbenzoic acid by UbiD and suggests a wider role for this cofactor in metabolism.
There is described an apparatus for measuring protein characteristics comprising an X-ray fluorescence (XRF) spectrometer comprising a source of polychromatic X-rays, an X-ray detector, a protein, a molecule that has been exposed to and at least weakly binds to the protein, a plurality of X-ray fluorescence signal data obtained by irradiating chemical elements in the protein and molecule with the polychromatic X-rays and a security system for maintaining records for the data from the plurality of X-ray fluorescence signal measurements. There is also described an x-ray microscope for measuring a sample.
描述了一种测量蛋白质特性的仪器,该仪器包括一个 X 射线荧光 (XRF) 光谱仪,其中包括一个多色 X 射线源、一个 X 射线探测器、一个蛋白质、一个已暴露于该蛋白质并至少与该蛋白质弱结合的分子、通过用多色 X 射线照射蛋白质和分子中的化学元素而获得的多个 X 射线荧光信号数据,以及一个用于维护多个 X 射线荧光信号测量数据记录的安全系统。此外,还介绍了一种用于测量样品的 X 射线显微镜。
X-ray microscope
申请人:XRpro Sciences, Inc.
公开号:EP2511844B1
公开(公告)日:2015-08-12
Advanced Drug Development and Manufacturing
申请人:XRpro Sciences, Inc.
公开号:US20150309021A1
公开(公告)日:2015-10-29
X-ray fluorescence (XRF) spectrometry has been used for detecting binding events and measuring binding selectivities between chemicals and receptors. XRF may also be used for estimating the therapeutic index of a chemical. For estimating the binding selectivities of a chemical versus chemical analogs, for measuring post translational modification of proteins, and for drug manufacturing.
Isofunctional Enzymes PAD1 and UbiX Catalyze Formation of a Novel Cofactor Required by Ferulic Acid Decarboxylase and 4-Hydroxy-3-polyprenylbenzoic Acid Decarboxylase
作者:Fengming Lin、Kyle L. Ferguson、David R. Boyer、Xiaoxia Nina Lin、E. Neil G. Marsh
DOI:10.1021/cb5008103
日期:2015.4.17
The decarboxylation of antimicrobial aromatic acids such as phenylacrylic acid (cinnamic acid) and ferulic acid by yeast requires two enzymes described as phenylacrylic acid decarboxylase (PAD1) and ferulic acid decarboxylase (FDC). These enzymes are of interest for various biotechnological applications, such as the production of chemical feedstocks from lignin under mild conditions. However, the specific role of each protein in catalyzing the decarboxylation reaction remains unknown. To examine this, we have overexpressed and purified both PAD1 and FDC from E. coli. We demonstrate that PAD1 is a flavin mononucleotide (FMN)-containing protein. However, it does not function as a decarboxylase. Rather, PAD1 catalyzes the formation of a novel, diffusible cofactor required by FDC for decarboxylase activity. Coexpression of FDC and PAD1 results in the production of FDC with high levels cofactor bound. Holo-FDC catalyzes the decarboxylation of phenylacrylic acid, coumaric acid and ferulic acid with apparent kcat ranging from 1.44.6 s(-1). The UV-visible and mass spectra of the cofactor indicate that it appears to be a novel, modified form of reduced FMN; however, its instability precluded determination of its structure. The E. coli enzymes UbiX and UbiD are related by sequence to PAD1 and FDC respectively and are involved in the decarboxylation of 4-hydroxy-3-octaprenylbenzoic acid, an intermediate in ubiquinone biosynthesis. We found that endogenous UbiX can also activate FDC. This implies that the same cofactor is required for decarboxylation of 4-hydroxy-3-polyprenylbenzoic acid by UbiD and suggests a wider role for this cofactor in metabolism.