Author: tianli

Cheng, Rui published the artcileA nucleotide-sensing endonuclease from the Gabija bacterial defense system, Name: Triisopropanolamine, the publication is Nucleic Acids Research (2021), 49(9), 5216-5229, database is CAplus and MEDLINE.

The arms race between bacteria and phages has led to the development of exquisite bacterial defense systems including a number of uncharacterized systems distinct from the well-known restriction-modification and CRISPR/Cas systems. Here, we report functional analyses of the GajA protein from the newly predicted Gabija system. The GajA protein is revealed as a sequence-specific DNA nicking endonuclease unique in that its activity is strictly regulated by nucleotide concentration NTP and dNTP at physiol. concentrations can fully inhibit the robust DNA cleavage activity of GajA. Interestingly, the nucleotide inhibition is mediated by an ATPase-like domain, which usually hydrolyzes ATP to stimulate the DNA cleavage when associated with other nucleases. These features suggest a mechanism of the Gabija defense in which an endonuclease activity is suppressed under normal conditions, while it is activated by the depletion of NTP and dNTP upon the replication and transcription of invading phages. This work highlights a concise strategy to utilize a DNA nicking endonuclease for phage resistance via nucleotide regulation.

Nucleic Acids Research published new progress about 122-20-3. 122-20-3 belongs to alcohols-buliding-blocks, auxiliary class Organic Pigment, name is Triisopropanolamine, and the molecular formula is C9H21NO3, Name: Triisopropanolamine.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Ruzicka, Frank published the artcileMethane monooxygenase catalyzed oxygenation of 1,1-dimethylcyclopropane. Evidence for radical and carbocationic intermediates, COA of Formula: C5H10O, the publication is Biochemistry (1990), 29(7), 1696-700, database is CAplus and MEDLINE.

Methane monooxygenase of Methylosinus trichosporium catalyzes the oxygenation of 1,1-dimethylcyclopropane in the presence of O₂ and NADH to (1-methylcyclopropyl)methanol(81%), 3-methyl-3-buten-1-ol (6%), and 1-methylbutanol (13%). Oxygenation by ¹⁸O₂ using the purified enzyme proceeds with incorporation of ¹⁸O into the products. Inasmuch as methane monooxygenase catalyzes the insertion of O from O₂ into a C-H bond of alkanes, (1-methylcyclopropyl)methanol appears to be a conventional oxygenation product. 3-Methyl-3-buten-1-ol is a rearrangement product that can be rationalized on the basis that enzymic oxygenation of 1,1-dimethylcyclopropane proceeds via the (1-methylcyclopropyl)carbinyl radical, which is expected to undergo rearrangement with ring opening to the homoallylic 3-methyl-3-buten-1-yl radical in competition with conventional with ring opening to the homoallylic 3-methyl-3-butenyl-1-yl radical in competition with conventional oxygenation. Oxygenation of the latter radical gives 3-methyl-3-buten-1-ol. 1-Methylcyclobutanol is a ring-expansion product, whose formation is best explained on the basis that the 1-methylcyclobutyl tertiary carbocation is an oxygenation intermediate. This cation would result from rearrangements of carbocations derived by 1-electron oxidation of either radical intermediate. The fact that both 3-methyl-3-buten-1-ol and 1-methylcyclobutanol are produced suggests that the oxygenation mechanism involves both radical and carbocationic intermediates. Radicals and carbocations can both be intermediates if they are connected by an electron-transfer step. A reasonable reaction sequence is one in which the cofactor (μ-oxo)diiron reacts with O₂ and 2-electrons to generate a H atom-abstracting species and an oxidizing agent. The H-abstracting species might be the enzymic radical or another species generated by the Fe complex and O₂. Oxygenation then could proceed by abstraction for a H atom from the substrate to form a radical, followed by electron transfer from the radical to the oxidizing species to form a carbocation. The carbocation would be quenched by O associated with the oxygenation cofactor to generate the product.

Biochemistry published new progress about 20117-47-9. 20117-47-9 belongs to alcohols-buliding-blocks, auxiliary class Aliphatic cyclic hydrocarbon,Alcohol, name is 1-Methylcyclobutan-1-ol, and the molecular formula is C5H10O, COA of Formula: C5H10O.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Moe, Luke A. published the artcileRemarkable Aliphatic Hydroxylation by the Diiron Enzyme Toluene 4-Monooxygenase in Reactions with Radical or Cation Diagnostic Probes Norcarane, 1,1-Dimethylcyclopropane, and 1,1-Diethylcyclopropane, Application of 1-Methylcyclobutan-1-ol, the publication is Biochemistry (2004), 43(50), 15688-15701, database is CAplus and MEDLINE.

Toluene 4-monooxygenase (T4MO) catalyzes the hydroxylation of toluene to yield 96% p-cresol. This diiron enzyme complex was used to oxidize norcarane (bicyclo[4.1.0]heptane), 1,1-dimethylcyclopropane, and 1,1-diethylcyclopropane, substrate analogs that can undergo diagnostic reactions upon the production of transient radical or cationic intermediates. Norcarane closely matches the shape and volume of the natural substrate toluene. Reaction of isoforms of the hydroxylase component of T4MO (T4moH) with different regiospecificities for toluene hydroxylation (k_cat ≈ 1.9-2.3 s^-1 and coupling efficiency ≈ 81-96%) revealed similar catalytic parameters for norcarane oxidation (k_cat ≈ 0.3-0.5 s^-1 and coupling efficiency ≈ 72%). The products included variable amounts of the un-rearranged isomeric norcaranols and cyclohex-2-enyl methanol, a product attributed to rearrangement of a radical oxidation intermediate. A ring-expansion product derived from the norcaranyl C-2 cation, cyclohept-3-enol, was not produced by either the natural enzyme or any of the T4moH isoforms tested. Comparative studies of 1,1-dimethylcyclopropane and 1,1-diethylcyclopropane, diagnostic substrates with differences in size and with ∼50-fold slower k_cat values, gave products consistent with both radical rearrangement and cation ring expansion. Examination of the isotopic enrichment of the incorporated O-atoms for all products revealed high-fidelity incorporation of an O-atom from O₂ in the un-rearranged and radical-rearranged products, while the O-atom found in the cation ring-expansion products was predominantly obtained by reaction with H₂O. The results show a divergence of radical and cation pathways for T4moH-mediated hydroxylation that can be dissected by diagnostic substrate probe rearrangements and by changes in the source of oxygen used for substrate oxygenation.

Biochemistry published new progress about 20117-47-9. 20117-47-9 belongs to alcohols-buliding-blocks, auxiliary class Aliphatic cyclic hydrocarbon,Alcohol, name is 1-Methylcyclobutan-1-ol, and the molecular formula is C5H10O, Application of 1-Methylcyclobutan-1-ol.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Gao, Lili published the artcileStepwise metabolic engineering of Gluconobacter oxydans WSH-003 for the direct production of 2-keto-L-gulonic acid from D-sorbitol, Recommanded Product: (3S,4R,5S)-3,4,5,6-Tetrahydroxy-2-oxohexanoic acid, the publication is Metabolic Engineering (2014), 30-37, database is CAplus and MEDLINE.

2-Keto-L-gulonic acid (2-KLG), the direct precursor of vitamin C, is currently produced by a two-step fermentation route from D-sorbitol. However, this route involves three bacteria, making the mix-culture system complicated and redundant. Thus, replacement of the conventional two-step fermentation process with a one-step process could be revolutionary in vitamin C industry. In this study, different combinations of five L-sorbose dehydrogenases (SDH) and two L-sorbosone dehydrogenases (SNDH) from Ketogulonicigenium vulgare WSH-001 were introduced into Gluconobacter oxydans WSH-003, an industrial strain used for the conversion of D-sorbitol to L-sorbose. The optimum combination produced 4.9 g/L of 2-KLG. In addition, 10 different linker peptides were used for the fusion expression of SDH and SNDH in G. oxydans. The best recombinant strain (G. oxydans/pGUC-k0203-GS-k0095) produced 32.4 g/L of 2-KLG after 168 h. Furthermore, biosynthesis of pyrroloquinoline quinine (PQQ), a cofactor of those dehydrogenases, was enhanced to improve 2-KLG production With the stepwise metabolic engineering of G. oxydans, the final 2-KLG production was improved to 39.2 g/L, which was 8.0-fold higher than that obtained using independent expression of the dehydrogenases. These results bring us closer to the final one-step industrial-scale production of vitamin C.

Metabolic Engineering published new progress about 526-98-7. 526-98-7 belongs to alcohols-buliding-blocks, auxiliary class Sugar Units,Other Sugar Units, name is (3S,4R,5S)-3,4,5,6-Tetrahydroxy-2-oxohexanoic acid, and the molecular formula is C6H10O7, Recommanded Product: (3S,4R,5S)-3,4,5,6-Tetrahydroxy-2-oxohexanoic acid.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Luo, Chengyi published the artcileEfficient biodegradation of phenanthrene using Pseudomonas stutzeri LSH-PAH1 with the addition of sophorolipids: Alleviation of biotoxicity and cometabolism studies, Formula: C11H8O3, the publication is Environmental Pollution (Oxford, United Kingdom) (2022), 119011, database is CAplus and MEDLINE.

Phenanthrene (PHE) is widely distributed, and it can cause genotoxicity in humans by interacting with enzymes in the body. A current challenge for PHE bioremediation is the inhibitory effect of biotoxic intermediates on bacterial growth. Notably, the aerobic biotransformation processes for PHE in the presence of sophorolipids have been poorly studied. Here, a PHE-degrading strain was isolated from sediments and identified as Pseudomonas stutzeri and named LSH-PAH1. It was observed that 1-naphthol (a biotoxic substance that can inhibit strain growth) was produced during the PHE metabolism process of LSH-PAH1. The biodegradation ratio increased from 21.4% to 91.7% within 48 h after the addition of sophorolipids. Unexpectedly, this addition accelerated the metabolic process for 1-naphthol rather than causing its accumulation. The cometabolism of 1-naphthol and sophorolipids alleviated the biotoxic effects for the strain, which was verified by gene expression anal. We identified a new PHE-degrading strain and provided a mechanism for PHE biodegradation using LSH-PAH1 with the addition of sophorolipids, which provides a reference for practical applications of the bioremediation of PHE and study of the cometabolism of biotoxic intermediates.

Environmental Pollution (Oxford, United Kingdom) published new progress about 86-48-6. 86-48-6 belongs to alcohols-buliding-blocks, auxiliary class Organic Pigment,Natural product, name is 1-Hydroxy-2-naphthoic acid, and the molecular formula is C11H8O3, Formula: C11H8O3.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Wang, Haiyong published the artcileSelective (ligno) cellulose hydrogenolysis to ethylene glycol and propyl monophenolics over Ni-W@C catalysts, Synthetic Route of 645-56-7, the publication is Cellulose (Dordrecht, Netherlands) (2020), 27(13), 7591-7605, database is CAplus.

The bi-functional Ni-W@C catalysts were prepared by one-pot reduction-carbonization method and used in hydrogenolysis of cellulose as well as raw lignocellulosic biomass to chems. The catalytic performance for cellulose conversion showed that it was more favorable for ethylene glycol (EG) production, obtaining the highest EG yield 60.1% over the Ni-W@C₇₀₀ catalyst. The Ni-W@C bimetallic catalysts are systematically characterized with BET, XRD, Raman, XPS, TEM techniques and experiments to probe the active catalytic sites of the catalysts. The effects of calcination temperature of Ni-W catalysts, reaction time, temperature and H₂ pressure on cellulose hydrogenolysis were investigated in detail. The Ni particles could lead to produce more W⁵⁺ active sites, which promotes the glucose retro-aldol condensation to break the target C-C bonds. Metallic Ni catalyzed C=O hydrogenation and C-C hydrogenolysis, which could also avoid the coke formation. The EG selectivity was dependent on the synergy of WO_x and Ni metal sites. In addition, this synergistic effect between the metal and WO_x could promote lignin component degradation in direct conversion of untreated raw lignocellulosic biomass, obtaining the Pr monophenolics including guaiacylpropane, syringylpropane and p-n-propylphenol with a total yield of 17.3 wt% besides EG.

Cellulose (Dordrecht, Netherlands) published new progress about 645-56-7. 645-56-7 belongs to alcohols-buliding-blocks, auxiliary class Liquid Crystal &OLED Materials, name is 4-Propylphenol, and the molecular formula is C20H17FO4S, Synthetic Route of 645-56-7.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Han, Yu published the artcileNon-target, suspect and target screening of chemicals of emerging concern in landfill leachates and groundwater in Guangzhou, South China, Product Details of C12H10O4S, the publication is Science of the Total Environment (2022), 155705, database is CAplus and MEDLINE.

Landfill sites have been regarded as a significant source of chems. of emerging concern (CECs) in groundwater. However, our understanding about the compositions of CECs in landfill leachate and adjacent groundwater is still very limited. Here we investigated the CECs in landfill leachates and groundwater of Guangzhou in South China by target, suspect and non-target anal. using high-resolution mass spectrometry (HRMS). A variety of CECs (n = 242), including pharmaceuticals (n = 64), pharmaceutical intermediates (n = 18), personal care products (n = 9), food additives (n = 18), industrial chems. (n = 82, e.g., flame retardants, plasticizers, antioxidants and catalysts), pesticides (n = 26), transformation products (n = 8) and other organic compounds (n = 17) were (tentatively) identified by non-target and suspect screening. 142 CECs were quantitated with target anal., and among them 37, 24 and 27 CECs were detected resp. in the raw leachate (272-1780μg/L), treated leachate (0.25-0.81μg/L) and groundwater (0.10-53.7μg/L). The CECs in the raw leachates were efficiently removed with the removal efficiencies greater than 88.7%. Acesulfame, bisphenol F and ketoprofen were the most abundant compounds in both treated leachate and groundwater. The CECs in groundwater was found most likely to be originated from the landfill sites. Our results highlight the importance of non-target screening in identifying CECs, and reveal the contamination risk of groundwater by landfill leachate.

Science of the Total Environment published new progress about 80-09-1. 80-09-1 belongs to alcohols-buliding-blocks, auxiliary class Ploymers, name is 4,4′-Sulfonyldiphenol, and the molecular formula is C12H10O4S, Product Details of C12H10O4S.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Liu, Caiyun published the artcileBinding Modes of Salicylic Acids to Titanium Oxide Molecular Surfaces, HPLC of Formula: 86-48-6, the publication is Chemistry – A European Journal (2020), 26(12), 2666-2674, database is CAplus and MEDLINE.

A set of titanium oxide clusters (TOCs) comprised of 4 to 16 Ti atoms are synthesized with substituted salicylates (SSAs). The interfacial coordination environment of these SSA/Ti oxide hybrids are surveyed and found to be limited to four binding modes, with the bridging chelate mode being the most common one. The SSA-functionalized TOCs show strong visible light absorption properties. The contribution of the SSAs in the frontier orbitals of the TOCs are analyzed by using TD-DFT calculations based on the mol. geometries determined by X-ray diffraction. For TOCs of relatively high O/Ti ratio, the SSAs narrow the band gap of the TOCs by contributing solely to the HOMOs. Both binding modes and locations of the SSAs are important for the roles of SSAs in changing the HOMOs and thereby the absorption onsets.

Chemistry – A European Journal published new progress about 86-48-6. 86-48-6 belongs to alcohols-buliding-blocks, auxiliary class Organic Pigment,Natural product, name is 1-Hydroxy-2-naphthoic acid, and the molecular formula is C11H8O3, HPLC of Formula: 86-48-6.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Zhao, Mingxing published the artcileHydrodeoxygenation of lignin-derived phenolics over facile prepared bimetallic RuCoN_x/NC, Application In Synthesis of 645-56-7, the publication is Fuel (2022), 121979, database is CAplus.

Cyclohexanols, promising oxygenated fuel additives and value-added chems., can be obtained by hydrodeoxygenation (HDO) of lignin-derived phenolics. Here, an N-doped bimetallic RuCoN_x/NC catalyst was facilely prepared for HDO by direct pyrolysis of chitin impregnated with precursors of Ru and Co. Characterization of RuCoN_x/NC with N₂ sorption, SEM (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), XPS and NH₃ temperature-programmed desorption (NH₃-TPD) reveal that the metallic particles of electron-deficient Ru species and electron-enriched Co species were uniformly anchored on the micro-mesoporous N-doped carbon matrix with high dispersion and nano-scale size. The abundant accessible active sites and continuous spillover of H from Ru to Co make RuCoN_x/NC an excellent HDO catalyst. 4-Propylguaiacol, a typical phenolic compound from lignin degradation, was hydrodeoxygenated into 92% 4-propylcyclohexanol over RuCoN_x/NC at 210°C. With temperature increasing, propylcyclohexane became the major product, possessing 95% selectivity at 280°C after 6 h. Reusability tests show that RuCoN_x/NC can be recycled four times without the loss of conversion and initial selectivity. HDO of other phenolic compounds confirms the general applicability of RuCoN_x/NC.

Fuel published new progress about 645-56-7. 645-56-7 belongs to alcohols-buliding-blocks, auxiliary class Liquid Crystal &OLED Materials, name is 4-Propylphenol, and the molecular formula is C4H5NS2, Application In Synthesis of 645-56-7.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts

Zhou, Chen published the artcileA Sc(OTf)₃ catalyzed dehydrogenative reaction of electron-rich (hetero)aryl nucleophiles with 9-aryl-fluoren-9-ols, Safety of 9-Phenyl-9H-xanthen-9-ol, the publication is Organic & Biomolecular Chemistry (2019), 17(44), 9615-9619, database is CAplus and MEDLINE.

A highly efficient dehydrogenative reaction of a series of (hetero)aryl nucleophiles with 9-aryl-fluoren-9-ols was realized by using only 2 mol% of Sc(OTf)₃ as a catalyst. The corresponding 9,9-diarylfluorenes I [R¹ = Me, Ph, 4-ClC₆H₄, etc.; R² = H, Br; R³ = 1H-indol-3-yl, benzofuran-2-yl, 2-methyl-1H-indol-3-yl, etc.] were obtained in up to 99% yield. The protocol exhibited high selectivity, mild reaction conditions and good substrate compatibility. This protocol was further highlighted by its applications in the construction of potential electroluminescent materials.

Organic & Biomolecular Chemistry published new progress about 596-38-3. 596-38-3 belongs to alcohols-buliding-blocks, auxiliary class Other Aromatic Heterocyclic,Benzene,Alcohol, name is 9-Phenyl-9H-xanthen-9-ol, and the molecular formula is C10H14O, Safety of 9-Phenyl-9H-xanthen-9-ol.

Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts