Open AccessPossible involvement of red pigments in defense against mercury in Pseudomonas K‐62
Author(s) -
Fujimori Hiroyuki,
Kiyono Masako,
Nobuhara Kazunori,
PanHou Hidemitsu
Publication year - 1996
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1996.tb08007.x
Subject(s) - mercury (programming language) , pigment , chemistry , environmental chemistry , computer science , organic chemistry , programming language
To study the physiological role of the red pigments in soil strain Pseudomonas K‐62, we isolated a red pigment‐deficient white mutant from the soil strain by treatment with mitomycin C and compared the phenotypic properties of the mutant and parent strain. The red pigments, which were classified as one of carotenoids based on their physicochemical properties, were separated into two groups, designated pigment A and B respectively on NH‐Chromatorex HPLC.The crude pigments and pigment B which could react with Hg 2+ in the wild‐type Pseudomonas K‐62 and its mercury‐resistant plasmid‐deficient strain were enhanced by the addition of Hg 2+ . The white mutant thus obtained showed a greater sensitivity to Hg 2+ than the wild‐type reddish strain despite containing the resistant plasmids. The major component in pigment B was identified by mass spectrometric analysis as 1‐hydroxy‐1‐methoxy‐1,2, 1′,2′,7′,8′‐hexahydro‐ψ,ψ‐caroten‐4‐one, a carotenoid monoketone. These results suggested that red pigments, especially pigment B, may account, at least partially, for defense against Hg 2+ in the bacterial environments.