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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

Coherence plot showing transcription factors (TFs) involved in the response to CORM-3versusiCORM-3 inhemAcells. The x-coordinate of each point represents the ‚Äúprofile difference‚ÄĚ between the two conditions (computed as 1 minus the absolute Pearson correlation coefficient between the two profiles), while the y-coordinate represents the change in magnitude of the response (computed as the difference of the norm of the two profiles). Hence, TFs whose response is similar in both magnitude and kinetics will be located near the origin of the coherence plot in quadrant C, while TFs in quadrant B of the plot respond very differently both in terms of kinetics and in terms of amplitude. The activity of the TF BaeR in hemA cells is similar in response to both iCORM-3 and CORM-3, whereas HNS and NarP respond differently when cells are exposed to iCORM-3 or CORM-3.
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f9: Coherence plot showing transcription factors (TFs) involved in the response to CORM-3versusiCORM-3 inhemAcells. The x-coordinate of each point represents the ‚Äúprofile difference‚ÄĚ between the two conditions (computed as 1 minus the absolute Pearson correlation coefficient between the two profiles), while the y-coordinate represents the change in magnitude of the response (computed as the difference of the norm of the two profiles). Hence, TFs whose response is similar in both magnitude and kinetics will be located near the origin of the coherence plot in quadrant C, while TFs in quadrant B of the plot respond very differently both in terms of kinetics and in terms of amplitude. The activity of the TF BaeR in hemA cells is similar in response to both iCORM-3 and CORM-3, whereas HNS and NarP respond differently when cells are exposed to iCORM-3 or CORM-3.

Mentions: We ran TFInfer separately on the CORM-3 and iCORM-3 data sets and devised an intuitive visualization method that highlights differences in the magnitude of the response, and differences in the kinetics of the response, to the two stimuli. Namely, for each TF, we plot on the abscissa the profile difference (computed as 1 minus the absolute Pearson correlation coefficient between the two profiles) versus the difference in magnitude of the response on the ordinate (computed as the absolute difference of the norms of the two profiles, Table 1 and Fig. 9). We term these plots coherence plots. Hence, TFs whose response is similar in both magnitude and kinetics will be located near the origin of the coherence plot, while TFs in the top right corner of the plot respond very differently in both kinetics and amplitude. Several of the regulators whose activity is inferred to underlie effects described in this paper feature in this analysis. Thus, CpxR, which appears in quadrant A of Figure 9, is a member of the two-component regulatory system CpxA/CpxR that combats extra-cytoplasmic protein-mediated toxicity by increasing the synthesis of the periplasmic protease DegP as well as that of CpxP protein. The position of CpxP in the matrix is consistent with the membrane disturbance elicited by CORM-3 but not iCORM-3 (Fig. 8). The response regulator BaeR, however, which confers resistance to novobiocin and bile salts by stimulating drug exporter gene expression is near the origin in the coherence plot (Fig. 9), indicating that its response is similar in terms of magnitude and kinetics when cells are exposed to iCORM-3 or CORM-3, and is not markedly upregulated (Fig. 7). In contrast, H-NS gave a low correlation coefficient for this comparison, indicating a specific response to CORM-3 (Fig. 9).


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)

Coherence plot showing transcription factors (TFs) involved in the response to CORM-3versusiCORM-3 inhemAcells. The x-coordinate of each point represents the ‚Äúprofile difference‚ÄĚ between the two conditions (computed as 1 minus the absolute Pearson correlation coefficient between the two profiles), while the y-coordinate represents the change in magnitude of the response (computed as the difference of the norm of the two profiles). Hence, TFs whose response is similar in both magnitude and kinetics will be located near the origin of the coherence plot in quadrant C, while TFs in quadrant B of the plot respond very differently both in terms of kinetics and in terms of amplitude. The activity of the TF BaeR in hemA cells is similar in response to both iCORM-3 and CORM-3, whereas HNS and NarP respond differently when cells are exposed to iCORM-3 or CORM-3.
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4492677&req=5

f9: Coherence plot showing transcription factors (TFs) involved in the response to CORM-3versusiCORM-3 inhemAcells. The x-coordinate of each point represents the ‚Äúprofile difference‚ÄĚ between the two conditions (computed as 1 minus the absolute Pearson correlation coefficient between the two profiles), while the y-coordinate represents the change in magnitude of the response (computed as the difference of the norm of the two profiles). Hence, TFs whose response is similar in both magnitude and kinetics will be located near the origin of the coherence plot in quadrant C, while TFs in quadrant B of the plot respond very differently both in terms of kinetics and in terms of amplitude. The activity of the TF BaeR in hemA cells is similar in response to both iCORM-3 and CORM-3, whereas HNS and NarP respond differently when cells are exposed to iCORM-3 or CORM-3.
Mentions: We ran TFInfer separately on the CORM-3 and iCORM-3 data sets and devised an intuitive visualization method that highlights differences in the magnitude of the response, and differences in the kinetics of the response, to the two stimuli. Namely, for each TF, we plot on the abscissa the profile difference (computed as 1 minus the absolute Pearson correlation coefficient between the two profiles) versus the difference in magnitude of the response on the ordinate (computed as the absolute difference of the norms of the two profiles, Table 1 and Fig. 9). We term these plots coherence plots. Hence, TFs whose response is similar in both magnitude and kinetics will be located near the origin of the coherence plot, while TFs in the top right corner of the plot respond very differently in both kinetics and amplitude. Several of the regulators whose activity is inferred to underlie effects described in this paper feature in this analysis. Thus, CpxR, which appears in quadrant A of Figure 9, is a member of the two-component regulatory system CpxA/CpxR that combats extra-cytoplasmic protein-mediated toxicity by increasing the synthesis of the periplasmic protease DegP as well as that of CpxP protein. The position of CpxP in the matrix is consistent with the membrane disturbance elicited by CORM-3 but not iCORM-3 (Fig. 8). The response regulator BaeR, however, which confers resistance to novobiocin and bile salts by stimulating drug exporter gene expression is near the origin in the coherence plot (Fig. 9), indicating that its response is similar in terms of magnitude and kinetics when cells are exposed to iCORM-3 or CORM-3, and is not markedly upregulated (Fig. 7). In contrast, H-NS gave a low correlation coefficient for this comparison, indicating a specific response to CORM-3 (Fig. 9).

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