Transport of -Lactate, -Lactate, and Glycolate by the LldP and GlcA Membrane Carriers of Escherichia coli

Núñez, Marı́a Felisa; Kwon, Ohsuk; Wilson, Thomas H.; Aguilar, Juan; Baldomà, Laura; Lin, E. C. C.

doi:10.1006/bbrc.2001.6255

Cited by 71 publications

(40 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…During glucose fermentation, D-lactate is formed by an NAD-linked oxidoreductase encoded by the monocistronic operon ldhA at min 30.5 (3). Under aerobic conditions, however, D-lactate can be scavenged from the medium by the membrane transport carriers LldP (L-lactate permease) and GlcA (glycolate permease) (27). The captured D-lactate is then converted back to pyruvate by a flavin adenine dinucleotide-dependent dehydrogenase encoded by the dld monocistronic operon at min 47.9.…”

Section: Resultsmentioning

confidence: 99%

“…Plasmid pLdh2 was transformed into strain ECL 5001 (20) (Table 1) to delete the ldhA gene by homologous recombination as described previously (21), yielding strain ECL 5201. Plasmid pDld2 (27) was then transformed into strain ECL 5201 to delete the dld gene by homologues recombination, yielding strain ECL 5202. Deletion of the ldhA and dld genes was confirmed by PCR.…”

Section: Construction Of Strainsmentioning

confidence: 99%

“…Since it has been reported previously that D-lactate uptake by E. coli cell suspensions reaches the steady state within 2 min of the start of incubation (17,27), samples (100 ml) were withdrawn at 0.5 and 5 min and filtered through 0.65-m-pore-size cellulose nitrate filters. The filters were washed with 4 ml of buffer A, placed in plastic vials, and counted in the presence of Emulsifier-safe (Packard, Meriden, Conn.).…”

Section: Construction Of Strainsmentioning

confidence: 99%

See 2 more Smart Citations

Effect of d -Lactate on the Physiological Activity of the ArcB Sensor Kinase in Escherichia coli

2004

Self Cite

View full text Add to dashboard Cite

The Arc two-component system, comprising the ArcB sensor kinase and the ArcA response regulator, modulates the expression of numerous genes in response to the respiratory growth conditions. Under anoxic growth conditions ArcB autophosphorylates and transphosphorylates ArcA, which in turn represses or activates its target operons. The anaerobic metabolite D-lactate has been shown to stimulate the in vitro autophosphorylating activity of ArcB. In this study, the in vivo effect of D-lactate on the kinase activity of ArcB was assessed. The results demonstrate that D-lactate does not act as a direct signal for activation of ArcB, as previously proposed, but acts as a physiologically significant effector that amplifies ArcB kinase activity.The Arc (anoxic redox control) two-component system is an important element in the complex transcriptional regulatory network that allows facultative anaerobic bacteria, such as Escherichia coli, to sense various respiratory growth conditions and adapt their gene expression accordingly (13,15,22). This system consists of the transmembrane sensor kinase ArcB and the cognate response regulator ArcA. The ArcB protein belongs to a subfamily of tripartite hybrid kinases, because it contains three catalytic domains: an N-terminal transmitter domain (H1) with a conserved His292 residue, a central receiver domain (D1) with a conserved Asp576 residue, and a C-terminal phosphotransfer domain (H2) with a conserved His717 residue (10, 15). Under reducing conditions, ArcB autophosphorylates at the expense of ATP and transphosphorylates ArcA via a His2923Asp5763His7173Asp54 phosphorelay (8,19). Phosphorylated ArcA (ArcA-P), in turn, represses the expression of many operons involved in respiratory metabolism and activates a few operons encoding proteins involved in fermentative metabolism (22,23). Under oxidizing conditions ArcB autophosphorylation is inhibited by the quinone electron carriers (7), and ArcA-P dephosphorylates via a reverse Asp543His7173Asp576 phosphorelay (8). Signal transduction by phosphorelay has also been reported for the Kin/Spo system of Bacillus subtilis (4), the BvgS/BvgA system of Bordetella pertussis (29), the TorS/TorR system of E. coli (16), and the Sln1p/Ypd1p/Ssk1p system of Saccharomyces cerevisiae (28). This complex phosphotransfer mechanism is believed to allow multiple levels of control for fine-tuning.It has been reported previously that the presence of certain fermentation intermediates, such as D-lactate, acetate, and pyruvate, accelerates the autophosphorylation activity of ArcB and enhances the subsequent transphosphorylation of ArcA (6, 11). However, no in vivo evidence has been obtained to support the physiological significance of such an effect. Furthermore, because the cellular metabolites mentioned above accumulate during anaerobiosis, it has been proposed that these compounds might act as the actual signals through which ArcB senses anaerobic environments in vivo (2, 11).Here we present the results of experiments designed to probe the in vivo effect of...

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Construction Of Strainsmentioning

confidence: 99%

Section: Construction Of Strainsmentioning

confidence: 99%

See 1 more Smart Citation

Effect of d -Lactate on the Physiological Activity of the ArcB Sensor Kinase in Escherichia coli

2004

Self Cite

View full text Add to dashboard Cite

show abstract

“…For transport assays, the cells were collected at the end of the exponential phase, washed twice, suspended in minimal medium (3) to a final density of 0.5 mg (dry weight)/ml, and placed at 25°C (20). The rate of uptake was assayed by diluting a radioactive substrate 10-fold with the cell suspension to a final concentration of 20 M. The radioactive substrates assayed were [ To analyze the effect of sodium on acetate transport, cells were collected, washed up to three times with potassium phosphate buffer (pH 7.0) containing 10 mM MgCl 2 , and suspended in the same buffer at a final cell density of 0.5 mg (dry weight)/ml.…”

Section: Methodsmentioning

confidence: 99%

“…The amino acid sequences of LldP and GlcA exhibit 65% identity and 80% similarity. Nonetheless, LldP is more effective in accumulating L-lactate, whereas GlcA is more effective in accumulating glycolate (20). Acetate, a two-carbon monocarboxylate, is not recognized by either of these permeases.…”

mentioning

confidence: 98%

The Gene yjcG , Cotranscribed with the Gene acs , Encodes an Acetate Permease in Escherichia coli

et al. 2003

Self Cite

View full text Add to dashboard Cite

We isolated an Escherichia coli mutant strain that suppresses the glycolate-negative phenotype of a strain deficient in both GlcA and LldP transporters of this compound. This suppressing phenotype was assigned to yjcG, a gene whose function was previously unknown, which was found to encode a membrane protein able to transport glycolate. On the basis of sequence similarity, the yjcG gene product was classified as a member of the sodium:solute symporter family. Northern experiments revealed that yjcG is cotranscribed with its neighbor, acs, encoding acetyl coenzyme A synthetase, which is involved in the scavenging acetate. The fortuitous presence of an IS2 element in acs, which impaired yjcG expression by polarity in our parental strain, allowed us to conclude that the alternative glycolate carrier became active after precise excision of IS2 in the suppressed strain. The finding that yjcG encodes a putative membrane carrier for glycolate and the cotranscription of yjcG with acs suggested that the primary function of the yjcG gene product (proposed gene name, actP) could be acetate transport and allowed us to define an operon involved in acetate metabolism. The time course of [1,2-14 C]acetate uptake and the results of a concentration kinetics analysis performed with cells expressing ActP or cells deficient in ActP supported the the hypothesis that this carrier is an acetate transporter and suggested that there may be another transport system for this monocarboxylate.

show abstract

Experimental evidence for growth advantage and metabolic shift stimulated by photophosphorylation of proteorhodopsin expressed in Escherichia coli at anaerobic condition

Wang

et al. 2015

Biotech & Bioengineering

View full text Add to dashboard Cite

Since solar light energy is the source of all renewable biological energy, the direct usage of light energy by bacterial cell factory has been a very attractive concept, especially using light energy to promote anaerobic fermentation growth and even recycle low-energy carbon source when energy is the limiting factor. Proteorhodopsin(PR), a light-driven proton pump proven to couple with ATP synthesis when expressed heterogeneously, is an interesting and simple option to enable light usage in engineered strains. However, although it was reported to influence fermentation in some cases, heterogeneous proteorhodopsin expression was never shown to support growth advantage or cause metabolic shift by photophosphorylation so far. Hereby, we presented the first experimental evidence that heterogeneously expressed proteorhodopsin can provide growth advantage and cause ATP-dependent metabolism shift of acetate and lactate changes in Escherichia coli at anaerobic condition. Those discoveries suggest further application potential of PR in anaerobic fermentation where energy is a limiting factor.

show abstract

Transport of -Lactate, -Lactate, and Glycolate by the LldP and GlcA Membrane Carriers of Escherichia coli

Cited by 71 publications

References 27 publications

Effect of d -Lactate on the Physiological Activity of the ArcB Sensor Kinase in Escherichia coli

Effect of d -Lactate on the Physiological Activity of the ArcB Sensor Kinase in Escherichia coli

The Gene yjcG , Cotranscribed with the Gene acs , Encodes an Acetate Permease in Escherichia coli

Experimental evidence for growth advantage and metabolic shift stimulated by photophosphorylation of proteorhodopsin expressed in Escherichia coli at anaerobic condition

Contact Info

Product

Resources

About