Chemical structure of cichorinotoxin, a cyclic lipodepsipeptide that is produced by Pseudomonas cichorii and causes varnish spots on lettuce

• Hidekazu Komatsu,
• Takashi Shirakawa,
• Takeo Uchiyama and
• Tsutomu Hoshino

Beilstein J. Org. Chem. 2019, 15, 299–309, doi:10.3762/bjoc.15.27

• alkaline hydrolysates, compounds A and B, were prepared. We discuss here the structure–activity relationships between the derivatives and their necrotic activities toward lettuce. Keywords: cichorinotoxin; lipodepsipeptide; necrotic lesion of lettuce; phytotoxin; Pseudomonas cichorii; Introduction

• infection are of great interest, but the infection mechanism remains unknown. We isolated a phytotoxin from the bacterial bodies of P. cichorii isolate YM8705 to clarify its mechanism of action. An injection of 750 pg of the isolated toxin caused necrotic lesions on lettuce midrib [5]. Furthermore, this

Opportunities and challenges for the sustainable production of structurally complex diterpenoids in recombinant microbial systems

• Katarina Kemper,
• Max Hirte,
• Markus Reinbold,
• Monika Fuchs and
• Thomas Brück

Beilstein J. Org. Chem. 2017, 13, 845–854, doi:10.3762/bjoc.13.85

• synthase domain indicating different catalytical properties. The natural product of PaFS is fusicocca-2,10(14)-diene, an intermediate in the biosynthesis of the phytotoxin fusicoccin A by P. amygdali. Interestingly, a recent work by Qin and co-workers [71] even revealed the conversion of a fungal diterpene

The direct oxidative diene cyclization and related reactions in natural product synthesis

• Juliane Adrian,
• Leona J. Gross and
• Christian B. W. Stark

Beilstein J. Org. Chem. 2016, 12, 2104–2123, doi:10.3762/bjoc.12.200

• isolated from the mould fungus Fusarium solani as a phytotoxin against barnyardgrass and duckweed in 1996 [30]. The Donohoe group presented a total synthesis in 2003 using an Os(VIII)-catalyzed oxidative cyclization as the key step [31] (Scheme 4). Several other total syntheses of that natural product did

Recent highlights in biosynthesis research using stable isotopes

• Jan Rinkel and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2015, 11, 2493–2508, doi:10.3762/bjoc.11.271

• [20]. It was investigated in the biosynthesis of the phytotoxin rhizoxin (4, Scheme 1), a potent antimitotic agent binding to β-tubulin from the bacterium Burkholderia rhizoxinica, which lives in symbiosis with the fungus Rhizopus microsporus [23]. The mechanism includes a Michael addition of a