Reductive Dechlorination of the Nitrogen Heterocyclic Herbicide Picloram

Author:

Ramanand K.1,Nagarajan A.1,Suflita Joseph M.1

Affiliation:

1. Department of Botany and Microbiology and Department of Chemistry and Biochemistry, 2 The University of Oklahoma, Norman, Oklahoma 73019

Abstract

The anaerobic biodegradation of picloram (3,5,6-trichloro-4-amino-2-pyridinecarboxylic acid) in freshwater sediment was favored under methanogenic conditions but not when sulfate or nitrate was available as a terminal electron acceptor. Under the former conditions, more than 85% of the parent substrate (340 μM) was removed from nonsterile incubations in 30 days, following a 50-day acclimation period. Concomitant with substrate decay, an intermediate transiently accumulated in the sediment slurries. By liquid chromatography-mass spectrometry, the intermediate was identified as an isomer of dichloro-4-amino-2-pyridinecarboxylic acid. Proton nuclear magnetic resonance evidence suggested that a chlorine was reductively removed from the parent substrate at the position meta to the nitrogen heteroatom. Upon continued incubation, the dechlorinated product was transformed into an unidentified compound which accumulated and resisted further decay. The addition of sulfate or bromoethanesulfonic acid to sediment slurries inhibited picloram dehalogenation, but molybdate reversed the inhibitory effect of sulfate on pesticide metabolism. These findings help clarify the fate of a halogenated nitrogen heterocyclic herbicide in anaerobic environments.

Publisher

American Society for Microbiology

Subject

Ecology,Applied Microbiology and Biotechnology,Food Science,Biotechnology

Reference25 articles.

1. Reductive dehalogenation of a nitrogen heterocyclic herbicide in anoxic aquifer slurries;Adrian N. R.;Appl. Environ. Microbiol.,1990

2. Agundis O. and R. Behrens. 1966. Effect of aerobic and anaerobic atmospheres on the rate of atrazine disappearance from the soil p. 70. Abstr. Annu. Meet. Weed Sci. Soc. Am. Champaign Ill.

3. Microbial metabolism of homocyclic and heterocyclic aromatic compounds under anaerobic conditions;Berry D. F.;Microbiol. Rev.,1987

4. Ring dechlorination of deethylsimazine by hydrolases from Rhodococcus corallinus;Cook A. M.;FEMS Microbiol. Lett.,1986

5. Reductive dechlorination of high concentrations of tetrachloroethene to ethene by an anaerobic enrichment culture in the absence of methanogenesis;DiStefano T. D.;Appl. Environ. Microbiol.,1991

Cited by 23 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3