Decomposition of low degradable chelating agent by marine bacteria bioremediation of marine environment

2001 Fiscal Year Final Research Report Summary

• Project/Area Number: 12660166
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: General fisheries
• Research Institution: Tokyo University of Fisheries
• Principal Investigator: IMADA Chiaki Tokyo Univ. of Fisheries, Associate Prof., 水産学部, 助教授 (90183011)
• Project Period (FY): 2000 – 2001
• Keywords: EDTA / Chelating agent / marine bacteria / Pseudoalteromonas

Research Abstract

Chelating agent such as ethylenediaminetetraacetic acid (EDTA)-decomposing bacteria were first isolated from marine environment and characterized. The rate of degradation of EDTA was measured by ion chromatography as ferric chelate. Out of 885 isolates from various sea areas, 8 strains isolated from various sea areas were found to decompose it. Among them, strain H6-2-4 had the highest ability to decompose it. The rate of degradation was approximately 30 % in seawater medium containing 1000 ppm of Fe-EDTA. The experiment using the intact cells revealed that the strain also had an ability to decompose various metal-EDTA chelates such as Ca, Cu and Mg. EDTA was converted into iminodiacetic acid, which was further cleaved into glycine in the second pathway. The strain was a Gram-negative motile rod with polar flagella and required seawater for its growth, which indicated that it was marine in origin. The strain was identified as Pseudoalteromonas atlantica based on the DNA-DNA hybridization with the type culture.