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Molybdenum cofactor-dependent resistance to N-hydroxylated base analogs in Escherichia coli is independent of MobA function.

ABSTRACT: Lack of molybdenum cofactor (MoCo) in Escherichia coli and related microorganisms was found to cause hypersensitivity to certain N-hydroxylated base analogs, such as HAP (6-N-hydroxylaminopurine). This observation has lead to a previous proposal that E. coli contains a molybdoenzyme capable of detoxifying such N-hydroxylated analogs. Here, we show that, unexpectedly, deletion of all known or putative molybdoenzymes in E. coli failed to reveal any base-analog sensitivity, suggesting that a novel type of MoCo-dependent activity is involved. Further, we establish that protection against the analogs does not require the common molybdopterin guanine-dinucleotide (MGD) form of the cofactor, but instead the guanosine monophosphate (GMP)-free version of MoCo (MPT) is sufficient.

SUBMITTER: Kozmin SG

PROVIDER: S-EPMC1934987 | biostudies-literature | 2007 Jun

REPOSITORIES: biostudies-literature

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Molybdenum cofactor-dependent resistance to N-hydroxylated base analogs in Escherichia coli is independent of MobA function.

Kozmin Stanislav G SG Schaaper Roel M RM

Mutation research 20070202 1-2

Lack of molybdenum cofactor (MoCo) in Escherichia coli and related microorganisms was found to cause hypersensitivity to certain N-hydroxylated base analogs, such as HAP (6-N-hydroxylaminopurine). This observation has lead to a previous proposal that E. coli contains a molybdoenzyme capable of detoxifying such N-hydroxylated analogs. Here, we show that, unexpectedly, deletion of all known or putative molybdoenzymes in E. coli failed to reveal any base-analog sensitivity, suggesting that a novel ...[more]

PMID: 17349664

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