caa a22 4500 469102179 CHVBK 20180323133047.0 cr unu---uuuuu 170328e19921201xx s 000 0 eng 10.1007/BF00240364 doi (NATIONALLICENCE)springer-10.1007/BF00240364 Characterization of an inducible, membrane-bound iminodiacetate dehydrogenase from Chelatobacter heintzii ATCC 29600 [Elektronische Daten] [Thomas Uetz, Thomas Egli] Iminodiacetate (IDA) is a xenobiotic intermediate common to both aerobic and anaerobic metabolism of nitrilotriacetate (NTA). It is formed by either NTA monooxygenase or NTA dehydrogenase. In this paper the detection and characterization of a membrane-bound iminodiacete dehydrogenase (IDA-DH) from Chelatobacter heintzii ATCC 29600 is reported, which oxidizes IDA to glycine and glyoxylate. Out of 15 compounds tested, IDA was the only substrate for the enzyme. Optimum activity of IDA-DH was found at pH 8.5 and 25°C, respectively, and the Km for IDA was found to be 8mM. Activity of the membrane-bound enzyme was inhibited by KCN, antimycine and dibromomethylisopropyl-benzoquinone. When inhibited by KCN IDA-DH was able to reduce the artificial electron acceptor iodonitrotetrazolium (INT). It was possible to extract IDA-DH from the membranes with 2% cholate, to reconstitute the enzyme into soybean phospholipid vesicles and to obtain IDA-DH activity (more than 50% recovery) using ubiquinone Q1 as the intermediate electron carrier and INT as the final electron acceptor. Growth experiments with different substrates revealed that in all NTA-degrading strains tested both NTA monooxygenase and IDA-DH were only expressed when the cells were grown on NTA or IDA. Furthermore, in Cb. heintzii ATCC 29600 growing exponentially on succinate and ammonia, addition of 0.4 g l-1 NTA led to the induction of the two enzymes within an hour and NTA was utilized simultaneously with succinate. The presence of IDA-DH was confirmed in ten different NTA-degrading strains belonging to three different genera. Kluwer Academic Publishers, 1993 membrane protein nationallicence biodegradation nationallicence iminodiacetate nationallicence iminodiacetate dehydrogenase nationallicence nitrilotriacetate (NTA) nationallicence ubiquinones nationallicence cA : component A nationallicence cB : component B nationallicence DBMIB : dibromomethylisopropyl-benzoquinone nationallicence HEPES : hydroxyethylpiperazinethanesulfonic acid nationallicence IDA : iminodiacetate, HN(CH2COOH)2 nationallicence IDA-DH : iminodiacetate dehydrogenase nationallicence INT : iodonitrotetrazolium chloride nationallicence NTA : nitrilotriacetate, N(CH2COOH)3 nationallicence NTA-MO : nitrilotriacetate monooxygenase nationallicence PMS : phenazine methosulphate nationallicence SDS-PAGE : sodium dodecylsulfate polyacrylamide gel electrophoresis nationallicence Suc-DH : succinate dehydrogenase nationallicence Uetz Thomas Federal Institute for Water Resources and Water Pollution Control (EAWAG), CH-8600, Dübendorf, Switzerland aut Egli Thomas Federal Institute for Water Resources and Water Pollution Control (EAWAG), CH-8600, Dübendorf, Switzerland aut Biodegradation Kluwer Academic Publishers 3/4(1992-12-01), 423-434 0923-9820 3:4<423 1992 3 10532 https://doi.org/10.1007/BF00240364 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00240364 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Uetz Thomas Federal Institute for Water Resources and Water Pollution Control (EAWAG), CH-8600, Dübendorf, Switzerland aut NATIONALLICENCE 700 1- Egli Thomas Federal Institute for Water Resources and Water Pollution Control (EAWAG), CH-8600, Dübendorf, Switzerland aut NATIONALLICENCE 773 0- Biodegradation Kluwer Academic Publishers 3/4(1992-12-01), 423-434 0923-9820 3:4<423 1992 3 10532 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer