The short (∼20 amino acid) C-terminal tails of both α- and β-tubulin that protrude from the microtubule are enriched in glutamic and aspartic acids, the surface of the microtubule possesses a net negative charge.

TLS Online TPP Program

#Id: 9738

#XL - R Botany

Members of the Poaceae family use benzoxazinoids an alkaloids derived from tryptophan as constitutively produced defensive secondary metabolites. 

TLS Online TPP Program

#Id: 9739

#XL - R Botany

Benzoxazinoids, especially 2,4-dihydroxy-1,4-benzoxazin-3-one (DIBOA) and its derivative 2,4-dihydroxy-7-methoxy-1,4-benzoxazin- 3-one (DIMBOA), are usually stored in the vacuole as glycosides coupled to d-glucose.

TLS Online TPP Program

#Id: 9740

#XL - R Botany

Cyanogenic glycosides represent a particularly toxic class of N-containing secondary metabolites. 

Upon tissue damage, these glycosides break down and release hydrogen cyanide (HCN). 

TLS Online TPP Program

#Id: 9741

#XL - R Botany

Cyanide inhibits cytochrome c oxidase in the mitochondria, which blocks the electron transport chain.

TLS Online TPP Program

#Id: 9742

#XL - R Botany

Amygdalin (the common cyanogenic glycoside found in the seeds of almonds, apricots, cherries, and peaches). 

Dhurrin from sorghum 

Linamarin and lotaustralin from cassava.

TLS Online TPP Program

#Id: 9743

#XL - R Botany

Glycosylated triterpenoid compound avenacin A1, found in oat (Avena sativa) roots The wheat root pathogen Gaeumannomyces graminis var. tritici is extremely sensitive to avenacins