1. Elucidation of the Biosynthetic Gene Cluster and the Post-PKS Modification Mechanism for Fostriecin in Streptomyces pulveraceus 
Rixiang Kong, Xuejiao Liu, Chun Su, Chunyan Ma, Rongguo Qiu, Li Tang 
Chemistry & Biology 
Volume 20, Issue 1, Pages (January 2013)
DOI: /j.chembiol
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2. Figure 1 Chemical Structures of Fostriecin and Its Related Compounds
These structurally related compounds share the same feature, a six-membered lactone with a cis-Δ2,3-double bond.
Chemistry & Biology  , 45-54DOI: ( /j.chembiol )
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3. Figure 2
Distribution of Sequenced Cosmids and Organization of the Fostriecin Biosynthetic Gene Cluster
The sequenced 73 kb DNA region from S. pulveraceus ATCC as represented by the four overlapping cosmids Cfos-F1-F4. The PKS modules for the fostriecin locus at two positions, with six additional tailoring enzymes centralized in the PKS. The orientation of the arrows indicates the direction of transcription.
Chemistry & Biology  , 45-54DOI: ( /j.chembiol )
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4. Figure 3
Proposed Fostriecin Polyketide Domain Organization and Biosynthetic Pathway in Streptomyces pulveraceus
Fostriecin polyketide biosynthesis uses a conventional PKS biosynthesis rule except that the ER domain in Module 1 is inactive. ACP, acyl carrier protein; AT, acyl transferase; DH, dehydratase; ER, enoyl reductase; KR, ketoreductase; KS, ketosynthase; TE, thioesterase.
Chemistry & Biology  , 45-54DOI: ( /j.chembiol )
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5. Figure 4
Disruption of the fosJ and fosH Genes and the Structure of Isolated Intermediates
(A) HPLC chromatograms of culture extract for ΔfosJ and ΔfosH gene disruption mutants, ΔfosJ complementation mutant, and wild-type strain. The mutant constructs are described in Figure S1 and Tables S1 and S2.
(B) The chemical structure of compounds 1–7 from ΔfosJ and ΔfosH mutant strains. NMR data are listed in Tables S3–S6, and the detailed structure elucidations are described in Text S1.
Chemistry & Biology  , 45-54DOI: ( /j.chembiol )
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6. Figure 5 In Vitro Enzyme Activity Assay of Purified FosH Protein: EH1
(A) Four standard compounds in a coinjection.
(B) EH1 enzyme catalyzing reaction analysis of compound 1.
(C) The control substrate reaction analysis of compound 1 without EH1 protein.
(D) EH1 enzyme catalyzing reaction analysis of PD114,631.
(E) The control substrate reaction analysis of PD114,631 without EH1 protein. The construct and confirmation of FosH heterologous expression system are shown in Figures S2 and S3.
Chemistry & Biology  , 45-54DOI: ( /j.chembiol )
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7. Figure 6
A Proposed Post-PKS Modification Pathway in the Biosynthesis of Fostriecin
The main post-PKS biosynthesis pathway is depicted in the box indicating by a solid arrow, then a shunt pathway occurs in the fosJ deletion mutant to produce compound 3, as indicated with a simple arrow. Compounds 1, 2, and 7 and PD113,270 are derived from the decomposition of compounds 4, 5, 6, and potentially compound 8, respectively, as depicted with a dashed arrow. The isolation of compounds 8 and 9 was completed in the ΔfosK and ΔfosM mutants, respectively.
Chemistry & Biology  , 45-54DOI: ( /j.chembiol )
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