ABSTRACT
Abstract Presence of the relatively new sulfonylurea herbicide monosulfuron-ester at 0.03-300 nmol/L affected the growth of two non-target nitrogen-fixing cyanobacteria (Anabaena flos-aquae and Anabaena azotica) and substantially inhibited in vitro Acetolactate synthase activity, with IC50 of 3.3 and 101.3 nmol/L for A. flos-aquae and A. azotica, respectively. Presenting in 30-300 nmol/L, it inhibited protein synthesis of the cyanobacteria with less amino acids produced as its concentration increased. Our findings support the view that monosulfuron-ester toxicity in both nitrogen-fixing cyanobacteria is due to its interference with protein metabolism via inhibition of branch-chain amino acid biosynthesis, and particularly Acetolactate synthase activity.
Subject(s)
Pyrimidines/toxicity , Sulfonylurea Compounds/toxicity , Anabaena/drug effects , Anabaena/metabolism , Dolichospermum flos-aquae/drug effects , Dolichospermum flos-aquae/metabolism , Esters/toxicity , Herbicides/toxicity , Nitrogen Fixation/drug effects , Anabaena/genetics , Dolichospermum flos-aquae/genetics , Amino Acids/metabolism , Nitrogen/metabolismABSTRACT
No presente estudo foi descrita e evidenciada a farmacologia das sulfoniluréias, no tratamento do diabetes mellitus do tipo II (insulino-independente). Apesar da sempre crescente utilizaçäo destas drogas na terapia do diabetes, principalmente pela sua praticidade e rapidez, näo se pode deixar de esquecer o balanço entre as dosagens, contra-indicaçöes e o aspecto geral, físico e mental do paciente. Além disso, so cuidados gerais, a orientaçä para uma dieta equilibrada, a prática de exercício e os cuidados com a higiene pessoal do indivíduo diabético sä necessários para que o tratamento alcance o sucesso esperado