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CO-Releasing Molecules Have Nonheme Targets in Bacteria: Transcriptomic, Mathematical Modeling and Biochemical Analyses of CORM-3 [Ru(CO)3Cl(glycinate)] Actions on a Heme-Deficient Mutant of Escherichia coli.

Wilson JL, Wareham LK, McLean S, Begg R, Greaves S, Mann BE, Sanguinetti G, Poole RK - Antioxid. Redox Signal. (2015)

Bottom Line: Carbon monoxide-releasing molecules (CORMs) are being developed with the ultimate goal of safely utilizing the therapeutic potential of CO clinically, including applications in antimicrobial therapy.A full understanding of the actions of CORMs is vital to understand their toxic effects.This is a vital step in exploiting the potential, already demonstrated, for using optimized CORMs in antimicrobial therapy.

View Article: PubMed Central - PubMed

Affiliation: 1 Department of Molecular Biology and Biotechnology, The University of Sheffield , Sheffield, United Kingdom .

ABSTRACT

Aims: Carbon monoxide-releasing molecules (CORMs) are being developed with the ultimate goal of safely utilizing the therapeutic potential of CO clinically, including applications in antimicrobial therapy. Hemes are generally considered the prime targets of CO and CORMs, so we tested this hypothesis using heme-deficient bacteria, applying cellular, transcriptomic, and biochemical tools.

Results: CORM-3 [Ru(CO)3Cl(glycinate)] readily penetrated Escherichia coli hemA bacteria and was inhibitory to these and Lactococcus lactis, even though they lack all detectable hemes. Transcriptomic analyses, coupled with mathematical modeling of transcription factor activities, revealed that the response to CORM-3 in hemA bacteria is multifaceted but characterized by markedly elevated expression of iron acquisition and utilization mechanisms, global stress responses, and zinc management processes. Cell membranes are disturbed by CORM-3.

Innovation: This work has demonstrated for the first time that CORM-3 (and to a lesser extent its inactivated counterpart) has multiple cellular targets other than hemes. A full understanding of the actions of CORMs is vital to understand their toxic effects.

Conclusion: This work has furthered our understanding of the key targets of CORM-3 in bacteria and raises the possibility that the widely reported antimicrobial effects cannot be attributed to classical biochemical targets of CO. This is a vital step in exploiting the potential, already demonstrated, for using optimized CORMs in antimicrobial therapy.

No MeSH data available.


Related in: MedlinePlus

Differential expression of genes involved in general stress responses, signal transduction, and zinc homeostasis. The heat map quantifies the changes elicited in selected genes; the “heat scale” at the right is expressed as the natural logarithm of the fold change. Shown are individual genes of the heme-deficient mutant of E. coli (hemA) and the corresponding wild-type grown anaerobically in defined medium after addition of 100 μM CORM-3 or, for the mutant only, 100 μM iCORM-3.
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f6: Differential expression of genes involved in general stress responses, signal transduction, and zinc homeostasis. The heat map quantifies the changes elicited in selected genes; the “heat scale” at the right is expressed as the natural logarithm of the fold change. Shown are individual genes of the heme-deficient mutant of E. coli (hemA) and the corresponding wild-type grown anaerobically in defined medium after addition of 100 μM CORM-3 or, for the mutant only, 100 μM iCORM-3.

Mentions: Some of the most highly altered genes in this study are involved in signal transduction and general stress response. Genes shown in Figure 6 were the most altered, and many have been reported to change in response to CORM-3 stress in previous transcriptomic studies (15, 51). Exceptions include the upregulation of hns, whose product is a global transcriptional regulator that responds to environmental changes and stress, and marked upregulation in the mutant of hmp, encoding a flavohemoglobin (70) with NO dioxygenase activity (26).


CO-Releasing Molecules Have Nonheme Targets in Bacteria: Transcriptomic, Mathematical Modeling and Biochemical Analyses of CORM-3 [Ru(CO)3Cl(glycinate)] Actions on a Heme-Deficient Mutant of Escherichia coli.

Wilson JL, Wareham LK, McLean S, Begg R, Greaves S, Mann BE, Sanguinetti G, Poole RK - Antioxid. Redox Signal. (2015)

Differential expression of genes involved in general stress responses, signal transduction, and zinc homeostasis. The heat map quantifies the changes elicited in selected genes; the “heat scale” at the right is expressed as the natural logarithm of the fold change. Shown are individual genes of the heme-deficient mutant of E. coli (hemA) and the corresponding wild-type grown anaerobically in defined medium after addition of 100 μM CORM-3 or, for the mutant only, 100 μM iCORM-3.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4492677&req=5

f6: Differential expression of genes involved in general stress responses, signal transduction, and zinc homeostasis. The heat map quantifies the changes elicited in selected genes; the “heat scale” at the right is expressed as the natural logarithm of the fold change. Shown are individual genes of the heme-deficient mutant of E. coli (hemA) and the corresponding wild-type grown anaerobically in defined medium after addition of 100 μM CORM-3 or, for the mutant only, 100 μM iCORM-3.
Mentions: Some of the most highly altered genes in this study are involved in signal transduction and general stress response. Genes shown in Figure 6 were the most altered, and many have been reported to change in response to CORM-3 stress in previous transcriptomic studies (15, 51). Exceptions include the upregulation of hns, whose product is a global transcriptional regulator that responds to environmental changes and stress, and marked upregulation in the mutant of hmp, encoding a flavohemoglobin (70) with NO dioxygenase activity (26).

Bottom Line: Carbon monoxide-releasing molecules (CORMs) are being developed with the ultimate goal of safely utilizing the therapeutic potential of CO clinically, including applications in antimicrobial therapy.A full understanding of the actions of CORMs is vital to understand their toxic effects.This is a vital step in exploiting the potential, already demonstrated, for using optimized CORMs in antimicrobial therapy.

View Article: PubMed Central - PubMed

Affiliation: 1 Department of Molecular Biology and Biotechnology, The University of Sheffield , Sheffield, United Kingdom .

ABSTRACT

Aims: Carbon monoxide-releasing molecules (CORMs) are being developed with the ultimate goal of safely utilizing the therapeutic potential of CO clinically, including applications in antimicrobial therapy. Hemes are generally considered the prime targets of CO and CORMs, so we tested this hypothesis using heme-deficient bacteria, applying cellular, transcriptomic, and biochemical tools.

Results: CORM-3 [Ru(CO)3Cl(glycinate)] readily penetrated Escherichia coli hemA bacteria and was inhibitory to these and Lactococcus lactis, even though they lack all detectable hemes. Transcriptomic analyses, coupled with mathematical modeling of transcription factor activities, revealed that the response to CORM-3 in hemA bacteria is multifaceted but characterized by markedly elevated expression of iron acquisition and utilization mechanisms, global stress responses, and zinc management processes. Cell membranes are disturbed by CORM-3.

Innovation: This work has demonstrated for the first time that CORM-3 (and to a lesser extent its inactivated counterpart) has multiple cellular targets other than hemes. A full understanding of the actions of CORMs is vital to understand their toxic effects.

Conclusion: This work has furthered our understanding of the key targets of CORM-3 in bacteria and raises the possibility that the widely reported antimicrobial effects cannot be attributed to classical biochemical targets of CO. This is a vital step in exploiting the potential, already demonstrated, for using optimized CORMs in antimicrobial therapy.

No MeSH data available.


Related in: MedlinePlus