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Papers by Jolanta Zakrzewska

PLoS ONE, 2012

Mycobacterium tuberculosis, the pathogen that causes tuberculosis, presumably utilizes fatty acid... more Mycobacterium tuberculosis, the pathogen that causes tuberculosis, presumably utilizes fatty acids as a major carbon source during infection within the host. Metabolism of even-chain-length fatty acids yields acetyl-CoA, whereas metabolism of oddchain-length fatty acids additionally yields propionyl-CoA. Utilization of these compounds by tubercle bacilli requires functional glyoxylate and methylcitrate cycles, respectively. Enzymes involved in both pathways are essential for M. tuberculosis viability and persistence during growth on fatty acids. However, little is known about regulatory factors responsible for adjusting the expression of genes encoding these enzymes to particular growth conditions. Here, we characterized the novel role of PrpR as a transcription factor that is directly involved in regulating genes encoding the key enzymes of methylcitrate (methylcitrate dehydratase [PrpD] and methylcitrate synthase [PrpC]) and glyoxylate (isocitrate lyase [Icl1]) cycles. Using cell-free systems and intact cells, we demonstrated an interaction of PrpR protein with prpDC and icl1 promoter regions and identified a consensus sequence recognized by PrpR. Moreover, we showed that an M. tuberculosis prpR-deletion strain exhibits impaired growth in vitro on propionate as the sole carbon source. Real-time quantitative reverse transcription-polymerase chain reaction confirmed that PrpR acts as a transcriptional activator of prpDC and icl1 genes when propionate is the main carbon source. Similar results were also obtained for a non-pathogenic Mycobacterium smegmatis strain. Additionally, we found that ramB, a prpR paralog that controls the glyoxylate cycle, is negatively regulated by PrpR. Our data demonstrate that PrpR is essential for the utilization of odd-chain-length fatty acids by tubercle bacilli. Since PrpR also acts as a ramB repressor, our findings suggest that it plays a key role in regulating expression of enzymes involved in both glyoxylate and methylcitrate pathways.

Open biology, Jan 27, 2013

Prior to bacterial cell division, the ATP-dependent polymerization of the cytoskeletal protein, P... more Prior to bacterial cell division, the ATP-dependent polymerization of the cytoskeletal protein, ParA, positions the newly replicated origin-proximal region of the chromosome by interacting with ParB complexes assembled on parS sites located close to the origin. During the formation of unigenomic spores from multi-genomic aerial hyphae compartments of Streptomyces coelicolor, ParA is developmentally triggered to form filaments along the hyphae; this promotes the accurate and synchronized segregation of tens of chromosomes into prespore compartments. Here, we show that in addition to being a segregation protein, ParA also interacts with the polarity protein, Scy, which is a component of the tip-organizing centre that controls tip growth. Scy recruits ParA to the hyphal tips and regulates ParA polymerization. These results are supported by the phenotype of a strain with a mutant form of ParA that uncouples ParA polymerization from Scy. We suggest that the ParA-Scy interaction coordinat...

Journal of Bacteriology, 2011

AdpA is a key regulator of morphological differentiation in Streptomyces . In contrast to Strepto... more AdpA is a key regulator of morphological differentiation in Streptomyces . In contrast to Streptomyces griseus , relatively little is known about AdpA protein functions in Streptomyces coelicolor . Here, we report for the first time the translation accumulation profile of the S. coelicolor adpA ( adpA Sc ) gene; the level of S. coelicolor AdpA (AdpA Sc ) increased, reaching a maximum in the early stage of aerial mycelium formation (after 36 h), and remained relatively stable for the next several hours (48 to 60 h), and then the signal intensity decreased considerably. AdpA Sc specifically binds the adpA Sc promoter region in vitro and in vivo , suggesting that its expression is autoregulated; surprisingly, in contrast to S. griseus , the protein presumably acts as a transcriptional activator. We also demonstrate a direct influence of AdpA Sc on the expression of several genes whose products play key roles in the differentiation of S. coelicolor : STI, a protease inhibitor; RamR, an ...

FEMS Microbiology Letters, 1984

The genome sizes of 13 Streptomyces and 2 Streptooertieillium strains were determined by the init... more The genome sizes of 13 Streptomyces and 2 Streptooertieillium strains were determined by the initial renaturation rate method described by De Ley and Gillis. The estimated genome sizes are within the range of 3.69 • 10 9 Da to 5.15 • 10 9 Da.

PLoS ONE, 2012

Mycobacterium tuberculosis, the pathogen that causes tuberculosis, presumably utilizes fatty acid... more Mycobacterium tuberculosis, the pathogen that causes tuberculosis, presumably utilizes fatty acids as a major carbon source during infection within the host. Metabolism of even-chain-length fatty acids yields acetyl-CoA, whereas metabolism of oddchain-length fatty acids additionally yields propionyl-CoA. Utilization of these compounds by tubercle bacilli requires functional glyoxylate and methylcitrate cycles, respectively. Enzymes involved in both pathways are essential for M. tuberculosis viability and persistence during growth on fatty acids. However, little is known about regulatory factors responsible for adjusting the expression of genes encoding these enzymes to particular growth conditions. Here, we characterized the novel role of PrpR as a transcription factor that is directly involved in regulating genes encoding the key enzymes of methylcitrate (methylcitrate dehydratase [PrpD] and methylcitrate synthase [PrpC]) and glyoxylate (isocitrate lyase [Icl1]) cycles. Using cell-free systems and intact cells, we demonstrated an interaction of PrpR protein with prpDC and icl1 promoter regions and identified a consensus sequence recognized by PrpR. Moreover, we showed that an M. tuberculosis prpR-deletion strain exhibits impaired growth in vitro on propionate as the sole carbon source. Real-time quantitative reverse transcription-polymerase chain reaction confirmed that PrpR acts as a transcriptional activator of prpDC and icl1 genes when propionate is the main carbon source. Similar results were also obtained for a non-pathogenic Mycobacterium smegmatis strain. Additionally, we found that ramB, a prpR paralog that controls the glyoxylate cycle, is negatively regulated by PrpR. Our data demonstrate that PrpR is essential for the utilization of odd-chain-length fatty acids by tubercle bacilli. Since PrpR also acts as a ramB repressor, our findings suggest that it plays a key role in regulating expression of enzymes involved in both glyoxylate and methylcitrate pathways.

Open biology, Jan 27, 2013

Prior to bacterial cell division, the ATP-dependent polymerization of the cytoskeletal protein, P... more Prior to bacterial cell division, the ATP-dependent polymerization of the cytoskeletal protein, ParA, positions the newly replicated origin-proximal region of the chromosome by interacting with ParB complexes assembled on parS sites located close to the origin. During the formation of unigenomic spores from multi-genomic aerial hyphae compartments of Streptomyces coelicolor, ParA is developmentally triggered to form filaments along the hyphae; this promotes the accurate and synchronized segregation of tens of chromosomes into prespore compartments. Here, we show that in addition to being a segregation protein, ParA also interacts with the polarity protein, Scy, which is a component of the tip-organizing centre that controls tip growth. Scy recruits ParA to the hyphal tips and regulates ParA polymerization. These results are supported by the phenotype of a strain with a mutant form of ParA that uncouples ParA polymerization from Scy. We suggest that the ParA-Scy interaction coordinat...

Journal of Bacteriology, 2011

AdpA is a key regulator of morphological differentiation in Streptomyces . In contrast to Strepto... more AdpA is a key regulator of morphological differentiation in Streptomyces . In contrast to Streptomyces griseus , relatively little is known about AdpA protein functions in Streptomyces coelicolor . Here, we report for the first time the translation accumulation profile of the S. coelicolor adpA ( adpA Sc ) gene; the level of S. coelicolor AdpA (AdpA Sc ) increased, reaching a maximum in the early stage of aerial mycelium formation (after 36 h), and remained relatively stable for the next several hours (48 to 60 h), and then the signal intensity decreased considerably. AdpA Sc specifically binds the adpA Sc promoter region in vitro and in vivo , suggesting that its expression is autoregulated; surprisingly, in contrast to S. griseus , the protein presumably acts as a transcriptional activator. We also demonstrate a direct influence of AdpA Sc on the expression of several genes whose products play key roles in the differentiation of S. coelicolor : STI, a protease inhibitor; RamR, an ...

FEMS Microbiology Letters, 1984

The genome sizes of 13 Streptomyces and 2 Streptooertieillium strains were determined by the init... more The genome sizes of 13 Streptomyces and 2 Streptooertieillium strains were determined by the initial renaturation rate method described by De Ley and Gillis. The estimated genome sizes are within the range of 3.69 • 10 9 Da to 5.15 • 10 9 Da.