Induction and Transcription Studies of the Dextransucrase Gene in Leuconostoc mesenteroides NRRL B-512F

ABSTRACT Dextransucrase production by Leuconostoc mesenteroidesNRRL B-512F in media containing carbon sources other than sucrose is reported for the first time. Dextransucrases were analyzed by gel electrophoresis and by an in situ activity assay. Their polymers and acceptor reaction products were also compared by 13C nuclear magnetic resonance and high-performance liquid chromatography techniques, respectively. From these analyses, it was found that, independently of the carbon source, L. mesenteroides NRRL B-512F produced dextransucrases of the same size and product specificity. The 5′ ends of dextransucrase mRNAs isolated from cells grown under different culture conditions were identical. Based on this evidence, we conclude that dextransucrases obtained from cells grown on the various carbon sources result from the transcription of the same gene. The control of expression occurs at this level. The low dextransucrase yields from cultures in d-glucose ord-fructose and the enhancement of dextransucrase gene transcription in the presence of sucrose suggest that an activating phenomenon may be involved in the expression mechanism. Dextransucrase mRNA has a size of approximately 4.8 kb, indicating that the gene is located in a monocistronic operon. The transcription start point was localized 34 bp upstream from the ATG start codon. The −10 and −35 sequences found, TATAAT and TTTACA, were highly homologous to the only glycosyltransferase promoter sequence reported for lactic acid bacteria.

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Metallasilsesquioxane-derived ultrathin porous carbon nanosheet 3D architectures via an “in situ dual templating” strategy for ultrafast sodium storage

Journal of Materials Chemistry A ◽

10.1039/d1ta00178g ◽

2021 ◽

Vol 9 (10) ◽

pp. 6423-6431

Author(s):

Xieji Lin ◽

Yue Dong ◽

Xiaohong Chen ◽

Haiyan Liu ◽

Zhaobin Liu ◽

...

Keyword(s):

Porous Carbon ◽

Carbon Sources ◽

Carbon Nanosheets ◽

Different Dimensions ◽

First Time ◽

Sodium Storage

It is the first time that metallasilsesquioxanes are introduced into the synthesis of porous carbon nanosheets. Lithium hepta(i-butyl)silsesquioxane trisilanolate is a multifunctional precursor for both carbon sources and templates with different dimensions.

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Effect of carbon sources on physicochemical properties of bacterial cellulose produced from Gluconacetobacter xylinus MTCC 7795

e-Polymers ◽

10.1515/epoly-2016-0047 ◽

2016 ◽

Vol 16 (4) ◽

pp. 331-336

Author(s):

Rushali Singh ◽

Ashwani Mathur ◽

Navendu Goswami ◽

Garima Mathur

Keyword(s):

Physicochemical Properties ◽

Bacterial Cellulose ◽

Specific Growth ◽

Carbon Sources ◽

Xrd Analysis ◽

Culture Conditions ◽

Shake Flask Culture ◽

Gluconacetobacter Xylinus ◽

X Ray ◽

First Time

AbstractIn this study, the effect of modified Hestrin Schramm (HS) medium supplemented with different carbon sources viz., glucose, fructose, galactose and lactic acid on the yield and physicochemical properties of bacterial cellulose (BC) produced from Gluconacetobacter xylinus strain MTCC 7795 in shake flask culture conditions was investigated. Growth studies indicated that all carbon sources supported the growth of bacteria, though specific growth rate and doubling time differs. Fructose gave the highest cellulose yield of 7.72 mg/ml after 130 h of fermentation, while yield in glucose and galactose supplemented medium were 4.49 mg/ml and 3.38 mg/ml, respectively. X-ray powder diffraction (XRD) analysis revealed that all BC samples were amorphous in comparison to commercial cellulose. Fourier transform infrared (FTIR) spectroscopic investigations of bacterial cellulose (BC) samples affirm the purity of the cellulose produced. No significant variations in physicochemical properties of cellulose samples produced with different carbon sources were observed. This study for the first time has investigated the effect of carbon sources on physicochemical properties of bacterial cellulose produced by G. xylinus MTCC 7795 and provides a strategy for economical production of BC with anticipated application in therapeutics and tissue engineering.

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RESEARCH PAPERS : EVALUATION OF IN-SITU EXTERNAL CARBON SOURCES FOR HIGH PERFORMANCE OF DENITRIFICATION IN GRAIN DISTILLERY WASTEWATER TREATMENT PLANT

Environmental Engineering Research ◽

10.4491/eer.2004.9.6.269 ◽

2004 ◽

Vol 9 (6) ◽

pp. 269-278 ◽

Cited By ~ 1

Author(s):

Sun-Jip Kim

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

High Performance ◽

Carbon Sources ◽

Treatment Plant ◽

Research Papers ◽

Distillery Wastewater

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Preparation of high performance perovskite-sensitized nanoporous titanium dioxide photoanodes by in situ method for use in perovskite solar cells

Journal of Materials Chemistry A ◽

10.1039/c4ta03384a ◽

2014 ◽

Vol 2 (39) ◽

pp. 16531-16537 ◽

Cited By ~ 57

Author(s):

Yaoming Xiao ◽

Gaoyi Han ◽

Yanping Li ◽

Miaoyu Li ◽

Yunzhen Chang ◽

...

Keyword(s):

Titanium Dioxide ◽

Solar Cells ◽

High Performance ◽

Perovskite Solar Cells ◽

In Situ Method ◽

First Time ◽

Nanoporous Titanium Dioxide

A high performance Perovskite-sensitized nanoporous TiO2photoanode is prepared for the first time by anin situtechnique for use in perovskite solar cells; potentially improving their efficency.

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A comparative study on LiFePO4/C by in-situ coating with different carbon sources for high-performance lithium batteries

Electrochimica Acta ◽

10.1016/j.electacta.2017.12.127 ◽

2018 ◽

Vol 261 ◽

pp. 96-103 ◽

Cited By ~ 14

Author(s):

Yanshuang Meng ◽

Jun Xia ◽

Lei Wang ◽

Gongrui Wang ◽

Fuliang Zhu ◽

...

Keyword(s):

Comparative Study ◽

Lithium Batteries ◽

High Performance ◽

Carbon Sources ◽

In Situ Coating

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In situ synthesis of Na2Ti7O15 nanotubes on a Ti net substrate as a high performance anode for Na-ion batteries

Chemical Communications ◽

10.1039/c5cc02612a ◽

2015 ◽

Vol 51 (45) ◽

pp. 9298-9300 ◽

Cited By ~ 42

Author(s):

Huan Li ◽

Hailong Fei ◽

Xin Liu ◽

Jie Yang ◽

Mingdeng Wei

Keyword(s):

High Performance ◽

Cycling Performance ◽

In Situ Synthesis ◽

First Time

Na2Ti7O15 nanotubes on a Ti net substrate were fabricated for the first time and exhibited excellent cycling performance.

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Critical Assessment of Glyco- and Phospholipid Separation by Using Silica Chromatography

Applied and Environmental Microbiology ◽

10.1128/aem.02817-13 ◽

2013 ◽

Vol 80 (1) ◽

pp. 360-365 ◽

Cited By ~ 23

Author(s):

Sandra M. Heinzelmann ◽

Nicole J. Bale ◽

Ellen C. Hopmans ◽

Jaap S. Sinninghe Damsté ◽

Stefan Schouten ◽

...

Keyword(s):

Fatty Acids ◽

High Performance ◽

Direct Detection ◽

Neutral Lipids ◽

Liquid Chromatography Mass Spectrometry ◽

Silica Column ◽

Betaine Lipids ◽

Intact Polar Lipids ◽

First Time

ABSTRACTPhospholipid-derived fatty acids (PLFAs) are commonly used to characterize microbial communitiesin situand the phylogenetic positions of newly isolated microorganisms. PLFAs are obtained through separation of phospholipids from glycolipids and neutral lipids using silica column chromatography. We evaluated the performance of this separation method for the first time using direct detection of intact polar lipids (IPLs) with high-performance liquid chromatography–mass spectrometry (HPLC-MS). We show that under either standard or modified conditions, the phospholipid fraction contains not only phospholipids but also other lipid classes such as glycolipids, betaine lipids, and sulfoquinovosyldiacylglycerols. Thus, commonly reported PLFA compositions likely are not derived purely from phospholipids and perhaps may not be representative of fatty acids present in living microbes.

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Characterization of Protocatechuate 4,5-Dioxygenase from Pseudarthrobacter phenanthrenivorans Sphe3 and In Situ Reaction Monitoring in the NMR Tube

International Journal of Molecular Sciences ◽

10.3390/ijms22179647 ◽

2021 ◽

Vol 22 (17) ◽

pp. 9647

Author(s):

Epameinondas Tsagogiannis ◽

Elpiniki Vandera ◽

Alexandra Primikyri ◽

Stamatia Asimakoula ◽

Andreas G. Tzakos ◽

...

Keyword(s):

Enzymatic Reaction ◽

Transcriptional Unit ◽

Pcr Analysis ◽

Reaction Products ◽

Gene Encoding ◽

Keto Form ◽

First Time ◽

Single Subunit

The current study aims at the functional and kinetic characterization of protocatechuate (PCA) 4,5-dioxygenase (PcaA) from Pseudarthrobacter phenanthrenivorans Sphe3. This is the first single subunit Type II dioxygenase characterized in Actinobacteria. RT-PCR analysis demonstrated that pcaA and the adjacent putative genes implicated in the PCA meta-cleavage pathway comprise a single transcriptional unit. The recombinant PcaA is highly specific for PCA and exhibits Michaelis–Menten kinetics with Km and Vmax values of 21 ± 1.6 μM and 44.8 ± 4.0 U × mg−1, respectively, in pH 9.5 and at 20 °C. PcaA also converted gallate from a broad range of substrates tested. The enzymatic reaction products were identified and characterized, for the first time, through in situ biotransformation monitoring inside an NMR tube. The PCA reaction product demonstrated a keto-enol tautomerization, whereas the gallate reaction product was present only in the keto form. Moreover, the transcriptional levels of pcaA and pcaR (gene encoding a LysR-type regulator of the pathway) were also determined, showing an induction when cells were grown on PCA and phenanthrene. Studying key enzymes in biodegradation pathways is significant for bioremediation and for efficient biocatalysts development.

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Benzothiazole Degradation by Rhodococcus pyridinovorans Strain PA: Evidence of a Catechol 1,2-Dioxygenase Activity

Applied and Environmental Microbiology ◽

10.1128/aem.68.12.6114-6120.2002 ◽

2002 ◽

Vol 68 (12) ◽

pp. 6114-6120 ◽

Cited By ~ 32

Author(s):

Nicolas Haroune ◽

Bruno Combourieu ◽

Pascale Besse ◽

Martine Sancelme ◽

Thorsten Reemtsma ◽

...

Keyword(s):

Ring Opening ◽

High Performance ◽

Reversed Phase ◽

Culture Conditions ◽

Ionization Mass ◽

Structure Detection ◽

Catechol 1,2 Dioxygenase ◽

Kinetics Of ◽

C Nmr

ABSTRACT The pathway for biodegradation of benzothiazole (BT) and 2-hydroxybenzothiazole (OBT) by Rhodococcus pyridinovorans strain PA was studied in detail. The kinetics of biodegradation were monitored by in situ 1H nuclear magnetic resonance (NMR) in parallel with reversed-phase high-performance liquid chromatography (HPLC). Successive oxidations from BT to OBT and then from OBT to dihydroxybenzothiazole were observed. Further insight was obtained by using a mutant strain with impaired ability to grow on BT and OBT. The precise structure of another intermediate was determined by in situ two-dimensional 1H-13C NMR and HPLC-electrospray ionization mass spectrometry; this intermediate was found to be a ring-opening product (a diacid structure). Detection of this metabolite, together with the results obtained by 1H and 19F NMR when cells were incubated with 3-fluorocatechol, demonstrated that a catechol 1,2-dioxygenase is involved in a pathway for biodegradation of BTs in this Rhodococcus strain. Our results show that catechol 1,2-dioxygenase and catechol 2,3-dioxygenase activities may both be involved in the biodegradation of BTs depending on the culture conditions.

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