Catabolic role of a three-component salicylate oxygenase from Sphingomonas yanoikuyae B1 in polycyclic aromatic hydrocarbon degradation.
Sphingomonas yanoikuyae B1 possesses several different multicomponent oxygenases involved in metabolizing aromatic compounds. Six different pairs of genes encoding large and small subunits of oxygenase iron-sulfur protein components have previously been identified in a gene cluster involved in the degradation of both monocyclic and polycyclic aromatic hydrocarbons. Insertional inactivation of one of the oxygenase large subunit genes, bphA1c, results in a mutant strain unable to grow on naphthalene, phenanthrene, or salicylate. The knockout mutant accumulates salicylate from naphthalene and 1-hydroxy-2-naphthoic acid from phenanthrene indicating the loss of salicylate oxygenase activity. Complementation experiments verify that the salicylate oxygenase in S. yanoikuyae B1 is a three-component enzyme consisting of an oxygenase encoded by bphA2cA1c, a ferredoxin encoded by the adjacent bphA3, and a ferredoxin reductase encoded by bphA4 located over 25kb away. Expression of bphA3-bphA2c-bphA1c genes in Escherichia coli demonstrated the ability of salicylate oxygenase to convert salicylate to catechol and 3-, 4-, and 5-methylsalicylate to methylcatechols.
Cho
Okyoung
O
Department of Biology, Institute of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea.
Choi
Ki Young
KY
Zylstra
Gerben J
GJ
Kim
Young-Soo
YS
Kim
Seong-Ki
SK
Lee
Joon H
JH
Sohn
Ho-Yong
HY
Kwon
Gi-Seok
GS
Kim
Young Min
YM
Kim
Eungbin
E
D001673:Biodegradation, Environmental; D002396:Catechols / Q000378:metabolism; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005287:Ferredoxin-NADP Reductase / Q000235:genetics / Q000378:metabolism; D005288:Ferredoxins / Q000235:genetics / Q000378:metabolism; D006841:Hydrocarbons, Aromatic / Q000737:chemistry / Q000378:metabolism; D005810:Multigene Family; D009281:Naphthalenes / Q000378:metabolism; D010105:Oxygenases / Q000235:genetics / Q000378:metabolism*; D010616:Phenanthrenes / Q000378:metabolism; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry / Q000378:metabolism*; D012459:Salicylates / Q000378:metabolism; D020578:Sphingomonas / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D013997:Time Factors
D002396:Catechols; D005288:Ferredoxins; D006841:Hydrocarbons, Aromatic; D009281:Naphthalenes; D010616:Phenanthrenes; D011084:Polycyclic Aromatic Hydrocarbons; D012459:Salicylates; D010105:Oxygenases; D005287:Ferredoxin-NADP Reductase