The aim of this work was to determine the ability of rhodococci to transform 3,5-dichloro-4-hydroxybenzonitrile (chloroxynil), 3,5-dibromo-4-hydroxybenzonitrile (bromoxynil), 3,5-diiodo-4-hydroxybenzonitrile (ioxynil) and 2,6-dichlorobenzonitrile (dichlobenil); to identify the products and determine their acute toxicities. Rhodococcus erythropolis A4 and Rhodococcus rhodochrous PA-34 converted benzonitrile herbicides into amides, but only the former strain was able to hydrolyze 2,6-dichlorobenzamide into 2,6-dichlorobenzoic acid, and produced also more of the carboxylic acids from the other herbicides compared to strain PA-34. Transformation of nitriles into amides decreased acute toxicities for chloroxynil and dichlobenil, but increased them for bromoxynil and ioxynil. The amides inhibited root growth in Lactuca sativa less than the nitriles but more than the acids. The conversion of the nitrile group may be the first step in the mineralization of benzonitrile herbicides but cannot be itself considered to be a detoxification.

• MeSH
• amidohydrolasy metabolismus   MeSH
• amidy metabolismus   toxicita   MeSH
• benzamidy metabolismus   MeSH
• biotransformace MeSH
• dehydratasy metabolismus   MeSH
• herbicidy chemie   metabolismus   MeSH
• hydrolýza MeSH
• jodbenzeny metabolismus   MeSH
• kořeny rostlin účinky léků   růst a vývoj   metabolismus   MeSH
• nitrily chemie   metabolismus   toxicita   MeSH
• Rhodococcus metabolismus   MeSH
• salát (hlávkový) účinky léků   růst a vývoj   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 2,6-dichlorobenzamide MeSH Prohlížeč
• amidase MeSH Prohlížeč
• amidohydrolasy MeSH
• amidy MeSH
• benzamidy MeSH
• benzonitrile MeSH Prohlížeč
• bromoxynil MeSH Prohlížeč
• chloroxynil MeSH Prohlížeč
• dehydratasy MeSH
• dichlobanil MeSH Prohlížeč
• herbicidy MeSH
• ioxynil MeSH Prohlížeč
• jodbenzeny MeSH
• nitrile hydratase MeSH Prohlížeč
• nitrily MeSH

This review deals with techniques and methods used in the study of the function and development of microorganisms occurring in soil with emphasis on the contributions of Czech Academician Ivan Málek and his coworkers or fellows (Jiří Macura, František Kunc) to the development of basic techniques used in soil microbiology. Early studies, including batch cultivation and respirometric techniques, as well as later developments of percolation and continuous-flow methods of cultivation of soil microorganisms are discussed. Recent developments in the application of analytical chemistry (HPLC or GC) and of molecular biological techniques to ecological questions that have revolutionized concepts in soil microbiology and microbial ecology are also briefly mentioned, including denaturing gradient gel electrophoresis (DGGE), temperature gradient gel electrophoresis (TGGE), phospholipid fatty acid analysis (PLFA) and others. The shift of soil microbiology from the study of individual microorganisms to entire microbial communities, including nonculturable species, is briefly discussed.

• MeSH
• Bacteria genetika   růst a vývoj   metabolismus   MeSH
• bakteriologické techniky přístrojové vybavení   metody   MeSH
• biologické markery MeSH
• fermentace MeSH
• půda analýza   MeSH
• půdní mikrobiologie * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• biologické markery MeSH
• půda MeSH

Bromoxynil (3,5-dibromo-4-hydroxybenzonitrile) was continuously added to chernozem (Haplic typic) soil inoculated with a suspension of Pseudomonas putida capable of cometabolic decomposition of the compound in a hetero-continuous-flow cultivation setup. In the steady state, when glucose or ribose were simultaneously added, 90 and 47% of the added herbicide was degraded per day, respectively. If the saccharides were absent, only 10-27% of the herbicide was decomposed. Addition and removal of glucose feeding resulted in an increase and decrease, respectively, of the degradation intensity, irrespective of the amount of the bacterial decomposers present. Two degradation products, 3,5-dibromo-4-hydroxy-benzamide and 3,5-dibromo-4-hydroxybenzoic acid, were formed during cultivation. The total amount of bromine-containing compounds was reduced only in the presence of glucose.

• MeSH
• biodegradace MeSH
• glukosa metabolismus   MeSH
• herbicidy metabolismus   MeSH
• koncentrace vodíkových iontů MeSH
• nitrily metabolismus   MeSH
• Pseudomonas putida metabolismus   MeSH
• půdní mikrobiologie MeSH
• ribosa metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bromoxynil MeSH Prohlížeč
• glukosa MeSH
• herbicidy MeSH
• nitrily MeSH
• ribosa MeSH