Phosphatase‐mediated heavy metal accumulation by a Citrobacter sp. and related enterobacteria

• Published in: FEMS microbiology letters 1994-08, Vol.121 (2), p.141-146
• Main Authors: Macaskie, L.E., Bonthrone, K.M., Rouch, D.A.
• Format: Article
• Language: English
• Subjects: Acid Phosphatase - metabolism; Amino Acid Sequence; Biological and medical sciences; Biotechnology; Citrobacter; Citrobacter - metabolism; Citrobacter sp; Enterobacter - metabolism; Environment and pollution; Fundamental and applied biological sciences. Psychology; Heavy metal accumulation; Industrial applications and implications. Economical aspects; Klebsiella pneumoniae; Lanthanum - analysis; Miscellaneous; Molecular Sequence Data; Morganella morganii; PhoN; Phosphatase; Providencia stuartii; Salmonella typhimurium; Salmonella typhimurium - metabolism; Sequence Alignment; Uranium - analysis
• ISSN: 0378-1097; 1574-6968
• DOI: 10.1111/j.1574-6968.1994.tb07090.x

A Citrobacter sp. was reported previously to accumulate heavy metals as cell‐bound heavy metal phosphates. Metal uptake is mediated by the activity of a periplasmic acid‐type phosphatase that liberates inorganic phosphate to provide the precipitant ligand for heavy metals presented to the cells. Amino acid sequencing of peptide fragments of the purified enzyme revealed significant homology to the phoN product (acid phosphatase) of some other enterobacteria. These organisms, together with Klebsiella pneumoniae, previously reported to produce acid phosphatase, were tested for their ability to remove uranium and lanthanum from challenge solutions supplemented with phosphatase substrate. The coupling of phosphate liberation to metal bioaccumulation was limited to the metal accumulating Citrobacter sp.; therefore the participation of species‐specific additional factors in metal bioaccumulation was suggested.