Mining and fine-tuning sugar uptake system for titer improvement of milbemycins in Streptomyces bingchenggensis

Abstract Background Caldicellulosiruptor kronotskyensis has gained interest for its ability to grow on various lignocellulosic biomass. The aim of this study was to investigate the growth profiles of C. kronotskyensis in the presence of mixtures of glucose–xylose. Recently, we characterized a diauxic-like pattern for C. saccharolyticus on lignocellulosic sugar mixtures. In this study, we aimed to investigate further whether C. kronotskyensis has adapted to uptake glucose in the disaccharide form (cellobiose) rather than the monosaccharide (glucose). Results Interestingly, growth of C. kronotskyensis on glucose and xylose mixtures did not display diauxic-like growth patterns. Closer investigation revealed that, in contrast to C. saccharolyticus, C. kronotskyensis does not possess a second uptake system for glucose. Both C. saccharolyticus and C. kronotskyensis share the characteristics of preferring xylose over glucose. Growth on xylose was twice as fast (μmax = 0.57 h−1) as on glucose (μmax = 0.28 h−1). A study of the sugar uptake was made with different glucose–xylose ratios to find a kinetic relationship between the two sugars for transport into the cell. High concentrations of glucose inhibited xylose uptake and vice versa. The inhibition constants were estimated to be KI,glu = 0.01 cmol L−1 and KI,xyl = 0.001 cmol L−1, hence glucose uptake was more severely inhibited by xylose uptake. Bioinformatics analysis could not exclude that C. kronotskyensis possesses more than one transporter for glucose. As a next step it was investigated whether glucose uptake by C. kronotskyensis improved in the form of cellobiose. Indeed, cellobiose is taken up faster than glucose; nevertheless, the growth rate on each sugar remained similar. Conclusions C. kronotskyensis possesses a xylose transporter that might take up glucose at an inferior rate even in the absence of xylose. Alternatively, glucose can be taken up in the form of cellobiose, but growth performance is still inferior to growth on xylose. Therefore, we propose that the catabolism of C. kronotskyensis has adapted more strongly to pentose rather than hexose, thereby having obtained a specific survival edge in thermophilic lignocellulosic degradation communities.

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The Hexose-Proton Cotransport System of Chlorella

The Journal of General Physiology ◽

10.1085/jgp.64.5.568 ◽

1974 ◽

Vol 64 (5) ◽

pp. 568-581 ◽

Cited By ~ 108

Author(s):

Ewald Komor ◽

Widmar Tanner

Keyword(s):

Sugar Transport ◽

Protonated Form ◽

Weak Acid ◽

Sugar Uptake ◽

Sugar Accumulation ◽

Maximal Velocity ◽

Uptake System ◽

High Affinity ◽

Ph Values ◽

Proton Concentration

The proton concentration in the medium affects the maximal velocity of sugar uptake with a Km of 0.3 mM (high affinity uptake). By decreasing the proton concentration a decrease in high affinity sugar uptake is observed, in parallel the activity of a low affinity uptake system (Km of 50 mM) rises. Both systems add up to 100%. The existence of the carrier in two conformational states (protonated and unprotonated) has been proposed therefore, the protonated form with high affinity to 6-deoxyglucose, the unprotonated form with low affinity. A plot of extrapolated Vmax values at low substrate concentration versus proton concentration results in a Km for protons of 0.14 µM, i.e. half-maximal protonation of the carrier is achieved at pH 6.85. The stoichiometry of protons cotransported per 6-deoxyglucose is close to 1 at pH 6.0–6.5. At higher pH values the stoichiometry continuously decreases; at pH 8.0 only one proton is cotransported per four molecules of sugar. Whereas the translocation of the protonated carrier is strictly dependent on sugar this coupling is less strict for the unprotonated form. Therefore at alkaline pH a considerable net efflux of accumulated sugar can occur. The dependence of sugar accumulation on pH has been measured. The decrease in accumulation with higher pH values can quantitatively be explained by the decrease in the amount of protonated carrier. The properties of the unprotonated carrier resemble strikingly the properties of carrier at the inner side of the membrane. The inside pH of Chlorella was measured with the weak acid 5,5-dimethyl-2, 4-oxazolidinedion (DMO). At an outside pH of 6.5 the internal pH was found to be 7.2. To explain the extent of sugar accumulation it has to be assumed that the membrane potential also contributes to active sugar transport in this alga.

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Aerococcus urinae and Globicatella sanguinis Persist in Polymicrobial Urethral Catheter Biofilms Examined in Longitudinal Profiles at the Proteomic Level

Biochemistry Insights ◽

10.1177/1178626419875089 ◽

2019 ◽

Vol 12 ◽

pp. 117862641987508 ◽

Cited By ~ 1

Author(s):

Yanbao Yu ◽

Tamara Tsitrin ◽

Shiferaw Bekele ◽

Vishal Thovarai ◽

Manolito G Torralba ◽

...

Keyword(s):

Urinary Tract ◽

Metal Ion ◽

Urethral Catheter ◽

Surface Proteins ◽

Transport Systems ◽

Sugar Uptake ◽

Uptake System ◽

Phosphotransferase System ◽

Rdna Sequencing ◽

Aerococcus Urinae

Aerococcus urinae ( Au) and Globicatella sanguinis ( Gs) are gram-positive bacteria belonging to the family Aerococcaceae and colonize the human immunocompromised and catheterized urinary tract. We identified both pathogens in polymicrobial urethral catheter biofilms (CBs) with a combination of 16S rDNA sequencing, proteomic analyses, and microbial cultures. Longitudinal sampling of biofilms from serially replaced catheters revealed that each species persisted in the urinary tract of a patient in cohabitation with 1 or more gram-negative uropathogens. The Gs and Au proteomes revealed active glycolytic, heterolactic fermentation, and peptide catabolic energy metabolism pathways in an anaerobic milieu. A few phosphotransferase system (PTS)–based sugar uptake and oligopeptide ABC transport systems were highly expressed, indicating adaptations to the supply of nutrients in urine and from exfoliating squamous epithelial and urothelial cells. Differences in the Au vs Gs metabolisms pertained to citrate lyase and utilization and storage of glycogen (evident only in Gs proteomes) and to the enzyme Xfp that degrades d-xylulose-5′-phosphate and the biosynthetic pathways for 2 protein cofactors, pyridoxal 6′-phosphate and 4′-phosphopantothenate (expressed only in Au proteomes). A predicted ZnuA-like transition metal ion uptake system was identified for Gs while Au expressed 2 LPXTG-anchored surface proteins, one of which had a predicted pilin D adhesion motif. While these proteins may contribute to fitness and virulence in the human host, it cannot be ruled out that Au and Gs fill a niche in polymicrobial biofilms without being the direct cause of injury in urothelial tissues.

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Involvement of Streptococcus gordonii Beta-Glucoside Metabolism Systems in Adhesion, Biofilm Formation, and In Vivo Gene Expression

Journal of Bacteriology ◽

10.1128/jb.186.13.4246-4253.2004 ◽

2004 ◽

Vol 186 (13) ◽

pp. 4246-4253 ◽

Cited By ~ 39

Author(s):

Ali O. Kiliç ◽

Lin Tao ◽

Yongshu Zhang ◽

Yu Lei ◽

Ali Khammanivong ◽

...

Keyword(s):

Biofilm Formation ◽

Heart Valves ◽

Sugar Uptake ◽

Uptake System ◽

Streptococcus Gordonii ◽

Induced Genes ◽

In Vitro Adhesion ◽

Plastic Surfaces

ABSTRACT Streptococcus gordonii genes involved in beta-glucoside metabolism are induced in vivo on infected heart valves during experimental endocarditis and in vitro during biofilm formation on saliva-coated hydroxyapatite (sHA). To determine the roles of beta-glucoside metabolism systems in biofilm formation, the loci of these induced genes were analyzed. To confirm the function of genes in each locus, strains were constructed with gene inactivation, deletion, and/or reporter gene fusions. Four novel systems responsible for beta-glucoside metabolism were identified, including three phosphoenolpyruvate-dependent phosphotransferase systems (PTS) and a binding protein-dependent sugar uptake system for metabolizing multiple sugars, including beta-glucosides. Utilization of arbutin and esculin, aryl-beta-glucosides, was defective in some mutants. Esculin and oligochitosaccharides induced genes in one of the three beta-glucoside metabolism PTS and in four other genetic loci. Mutation of genes in any of the four systems affected in vitro adhesion to sHA, biofilm formation on plastic surfaces, and/or growth rate in liquid medium. Therefore, genes associated with beta-glucoside metabolism may regulate S. gordonii in vitro adhesion, biofilm formation, growth, and in vivo colonization.

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Simulation of a high- and low-affinity sugar-uptake system in Chlorella by a pH-dependent change in the Km of the uptake system

Planta ◽

10.1007/bf00383869 ◽

1975 ◽

Vol 123 (2) ◽

pp. 195-198 ◽

Cited By ~ 22

Author(s):

E. Komor ◽

W. Tanner

Keyword(s):

Sugar Uptake ◽

Uptake System ◽

Dependent Change ◽

Ph Dependent

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Coupling Physiology and Gene Regulation in Bacteria: The Phosphotransferase Sugar Uptake System Delivers the Signals

The Science of Nature ◽

10.1007/s001140050555 ◽

1998 ◽

Vol 85 (12) ◽

pp. 583-592 ◽

Cited By ~ 48

Author(s):

Jörg Stülke ◽

Wolfgang Hillen

Keyword(s):

Gene Regulation ◽

Sugar Uptake ◽

Uptake System

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Characterization of Streptococcus mutans Strains Deficient in EIIABMan of the Sugar Phosphotransferase System

Applied and Environmental Microbiology ◽

10.1128/aem.69.8.4760-4769.2003 ◽

2003 ◽

Vol 69 (8) ◽

pp. 4760-4769 ◽

Cited By ~ 68

Author(s):

Jacqueline Abranches ◽

Yi-Ywan M. Chen ◽

Robert A. Burne

Keyword(s):

Streptococcus Mutans ◽

Type Strain ◽

Wild Type Strain ◽

Sugar Transport ◽

Fold Increase ◽

Sugar Uptake ◽

Uptake System ◽

Oral Streptococci ◽

Wild Type ◽

Phosphotransferase System

ABSTRACT The phosphoenolpyruvate:sugar phosphotransferase system (PTS) is the major sugar uptake system in oral streptococci. The role of EIIABMan (encoded by manL) in gene regulation and sugar transport was investigated in Streptococcus mutans UA159. The manL knockout strain, JAM1, grew more slowly than the wild-type strain in glucose but grew faster in mannose and did not display diauxic growth, indicating that EIIABMan is involved in sugar uptake and in carbohydrate catabolite repression. PTS assays of JAM1, and of strains lacking the inducible (fruI) and constitutive (fruCD) EII fructose, revealed that S. mutans EIIABMan transported mannose and glucose and provided evidence that there was also a mannose-inducible or glucose-repressible mannose PTS. Additionally, there appears to be a fructose PTS that is different than FruI and FruCD. To determine whether EIIABMan controlled expression of the known virulence genes, glucosyltransferases (gtfBC) and fructosyltransferase (ftf) promoter fusions of these genes were established in the wild-type and EIIABMan-deficient strains. In the manL mutant, the level of chloramphenicol acetyltransferase activity expressed from the gtfBC promoter was up to threefold lower than that seen with the wild-type strain at pH 6 and 7, indicating that EIIABMan is required for optimal expression of gtfBC. No significant differences were observed between the mutant and the wild-type background in ftf regulation, with the exception that under glucose-limiting conditions at pH 7, the mutant exhibited a 2.1-fold increase in ftf expression. Two-dimensional gel analysis of batch-grown cells of the EIIABMan-deficient strain indicated that the expression of at least 38 proteins was altered compared to that seen with the wild-type strain, revealing that EIIABMan has a pleiotropic effect on gene expression.

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Characterization of Simultaneous Uptake of Xylose and Glucose in Caldicellulosiruptor Kronotskyensis for Optimal Hydrogen Production

10.21203/rs.3.rs-151977/v1 ◽

2021 ◽

Author(s):

Thitiwut Vongkampang ◽

Krishnan Sreeni ◽

Jonathan Engvall ◽

Carl Grey ◽

Ed van Niel

Keyword(s):

Glucose Uptake ◽

Bioinformatic Analysis ◽

Growth Patterns ◽

Sugar Uptake ◽

Uptake System ◽

Sugar Mixtures ◽

Xylose Uptake ◽

Growth Profiles ◽

High Concentrations

Abstract BackgroundCaldicellulosiruptor kronotskyensis has gained interest for its ability to grow on various lignocellulosic biomass. The aim of this study was to investigate the growth profiles of C . kronotskyensis in the presence of mixtures of glucose-xylose. Recently, we characterized a diauxic-like pattern for C. saccharolyticus on lignocellulosic sugar mixtures. In this study we aimed to investigated further whether C . kronotskyensis has adapted to uptake glucose in the disaccharide form (cellobiose) rather than the monosaccharide (glucose). ResultsInterestingly, growth of C . kronotskyensis on glucose and xylose mixtures did not display diauxic-like growth patterns. Closer investigation revealed that, in contrast to C. saccharolyticus , C . kronotskyensis does not possess a second uptake system for glucose. Both C. saccharolyticus and C . kronotskyensis share the characteristics of preferring xylose over glucose. Growth on xylose was twice as fast (μ max = 0.57 h -1 ) as on glucose (μ max = 0.28 h -1 ). It was found that C . kronotskyensis takes up glucose and xylose simultaneously with the same transporter. A study of the sugar uptake was made with different glucose-xylose ratios to find a kinetic relationship between the two sugars for transport into the cell. High concentrations of glucose inhibited xylose uptake and vice versa. The inhibition constants were estimated to be K I,glu = 0.01 cmol·L -1 and K I,xyl = 0.001 cmol·L -1 , hence glucose uptake was more severely inhibited by xylose uptake. Bioinformatic analysis indicated the lack of another sugar uptake system in C . kronotskyensis as compared to C. saccharolyticus . Therefore, it was investigated whether glucose uptake by C . kronotskyensis was in the form of cellobiose. Indeed, cellobiose is taken up faster than glucose, nevertheless, the growth rate on each sugar remained similar. ConclusionsC . kronotskyensis possesses a xylose transporter that might take up glucose at an inferior rate even in the absence of xylose. Alternatively, glucose can be taken up in the form of cellobiose, but growth performance is still inferior to growth on xylose. Therefore, we propose that the catabolism of C . kronotskyensis has adapted more strongly to pentose rather than hexose thereby having obtained a specific survival edge in thermophilic lignocellulosic degradation communities.

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