Biodegradation of the allelopathic chemical m-tyrosine by Bacillus aquimaris SSC5 involves the homogentisate central pathway.
m-Tyrosine is an amino acid analogue, exuded from the roots of fescue grasses, which acts as a potent allelopathic and a broad spectrum herbicidal chemical. Although the production and toxic effects of m-tyrosine are known, its microbial degradation has not been documented yet. A soil microcosm stud...
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2013-01-01
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| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC3788032?pdf=render |
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| author | Fazlurrahman Khan Munesh Kumari Swaranjit Singh Cameotra |
| author_facet | Fazlurrahman Khan Munesh Kumari Swaranjit Singh Cameotra |
| author_sort | Fazlurrahman Khan |
| collection | DOAJ |
| description | m-Tyrosine is an amino acid analogue, exuded from the roots of fescue grasses, which acts as a potent allelopathic and a broad spectrum herbicidal chemical. Although the production and toxic effects of m-tyrosine are known, its microbial degradation has not been documented yet. A soil microcosm study showed efficient degradation of m-tyrosine by the inhabitant microorganisms. A bacterial strain designated SSC5, that was able to utilize m-tyrosine as the sole source of carbon, nitrogen, and energy, was isolated from the soil microcosm and was characterized as Bacillus aquimaris. Analytical methods such as HPLC, GC-MS, and (1)H-NMR performed on the resting cell samples identified the formation of 3-hydroxyphenylpyruvate (3-OH-PPA), 3-hydroxyphenylacetate (3-OH-PhAc), and homogentisate (HMG) as major intermediates in the m-tyrosine degradation pathway. Enzymatic assays carried out on cell-free lysates of m-tyrosine-induced cells confirmed transamination reaction as the first step of m-tyrosine degradation. The intermediate 3-OH-PhAc thus obtained was further funneled into the HMG central pathway as revealed by a hydroxylase enzyme assay. Subsequent degradation of HMG occurred by ring cleavage catalyzed by the enzyme homogentisate 1, 2-dioxygenase. This study has significant implications in terms of understanding the environmental fate of m-tyrosine as well as regulation of its phytotoxic effect by soil microorganisms. |
| first_indexed | 2024-12-21T17:13:48Z |
| format | Article |
| id | doaj.art-b81afd50d5194630807bb1984e6c370b |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-21T17:13:48Z |
| publishDate | 2013-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-b81afd50d5194630807bb1984e6c370b2022-12-21T18:56:20ZengPublic Library of Science (PLoS)PLoS ONE1932-62032013-01-01810e7592810.1371/journal.pone.0075928Biodegradation of the allelopathic chemical m-tyrosine by Bacillus aquimaris SSC5 involves the homogentisate central pathway.Fazlurrahman KhanMunesh KumariSwaranjit Singh Cameotram-Tyrosine is an amino acid analogue, exuded from the roots of fescue grasses, which acts as a potent allelopathic and a broad spectrum herbicidal chemical. Although the production and toxic effects of m-tyrosine are known, its microbial degradation has not been documented yet. A soil microcosm study showed efficient degradation of m-tyrosine by the inhabitant microorganisms. A bacterial strain designated SSC5, that was able to utilize m-tyrosine as the sole source of carbon, nitrogen, and energy, was isolated from the soil microcosm and was characterized as Bacillus aquimaris. Analytical methods such as HPLC, GC-MS, and (1)H-NMR performed on the resting cell samples identified the formation of 3-hydroxyphenylpyruvate (3-OH-PPA), 3-hydroxyphenylacetate (3-OH-PhAc), and homogentisate (HMG) as major intermediates in the m-tyrosine degradation pathway. Enzymatic assays carried out on cell-free lysates of m-tyrosine-induced cells confirmed transamination reaction as the first step of m-tyrosine degradation. The intermediate 3-OH-PhAc thus obtained was further funneled into the HMG central pathway as revealed by a hydroxylase enzyme assay. Subsequent degradation of HMG occurred by ring cleavage catalyzed by the enzyme homogentisate 1, 2-dioxygenase. This study has significant implications in terms of understanding the environmental fate of m-tyrosine as well as regulation of its phytotoxic effect by soil microorganisms.http://europepmc.org/articles/PMC3788032?pdf=render |
| spellingShingle | Fazlurrahman Khan Munesh Kumari Swaranjit Singh Cameotra Biodegradation of the allelopathic chemical m-tyrosine by Bacillus aquimaris SSC5 involves the homogentisate central pathway. PLoS ONE |
| title | Biodegradation of the allelopathic chemical m-tyrosine by Bacillus aquimaris SSC5 involves the homogentisate central pathway. |
| title_full | Biodegradation of the allelopathic chemical m-tyrosine by Bacillus aquimaris SSC5 involves the homogentisate central pathway. |
| title_fullStr | Biodegradation of the allelopathic chemical m-tyrosine by Bacillus aquimaris SSC5 involves the homogentisate central pathway. |
| title_full_unstemmed | Biodegradation of the allelopathic chemical m-tyrosine by Bacillus aquimaris SSC5 involves the homogentisate central pathway. |
| title_short | Biodegradation of the allelopathic chemical m-tyrosine by Bacillus aquimaris SSC5 involves the homogentisate central pathway. |
| title_sort | biodegradation of the allelopathic chemical m tyrosine by bacillus aquimaris ssc5 involves the homogentisate central pathway |
| url | http://europepmc.org/articles/PMC3788032?pdf=render |
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