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1.
Int J Biol Macromol ; 281(Pt 3): 136406, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39389498

RESUMEN

Lignin is a promising feedstock for producing vanillin, one of the most extensively used flavor enhancers. However, the biotransformation performance of lignin derivatives into vanillin is still unsatisfactory. In this study, an efficient conversion strategy of lignin into vanillin was established by employing engineered Saccharomyces cerevisiae as a whole-cell biocatalyst. Optimization of cell culture media and whole-cell bioconversion improved the production efficiency of vanillin. The vanillin titer reached 15.3 mM with a molar yield of 71 % in fed-batch fermentation mode, while incorporating in-situ product separation, demonstrated a remarkable 2.6-fold increase. The whole-cell bioconversion, coupled with in-situ separation, successfully converted real lignin hydrolysate into a record vanillin titer of 21.1 mM, equivalent to 1.8 mg of vanillin per gram of wheat bran biomass. The whole-cell bioconversion process integrated in-situ product separation, represents a sustainable approach for vanillin production and offers a promising pathway for lignin valorization.

2.
Mol Biotechnol ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261347

RESUMEN

The growth, development, and milk production traits of dairy goats, which are important sources of high-quality animal protein, are significantly influenced by a combination of genetic and environmental factors. It is imperative to identify key genetic loci that govern economically valuable traits in order to enhance breeding programs. Despite advancements in genomic technologies, there are still gaps in knowledge regarding the interplay between genetic factors and environmental influences, particularly in relation to the regulation of milk production and quality. Therefore, the aim of this paper was to synthesize advancements in the genetic and environmental factors affecting milk production and quality in dairy goats and identify key regulatory mechanisms. This review summarizes the recent progress on the identification of genes associated with milk production traits using whole-genome resequencing, the use of transcriptomic profiling to identify genes linked to milk production, the exploration of regulatory mechanisms of lipid metabolism in goat mammary epithelial cells, and the evaluation of the influence of nutritional factors on milk quality. A comprehensive understanding of these interactions is essential for enhancing breeding strategies and ensuring the sustainability of dairy goat farming. Future research should incorporate multi-omics approaches to unravel the intricate regulatory processes governing milk production and adapt practices to meet global demand while upholding economic and environmental sustainability.

3.
Trends Biotechnol ; 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39299833

RESUMEN

Genome design is the foundation of genome synthesis, which provides a new platform for deepening our understanding of biological systems by exploring the fundamental components and structure of the genome. Artificial genome designs can endow unnatural genomes with desired functions. We provide a comprehensive overview of genome design principles ranging from DNA sequences to the 3D structure of chromosomes. Furthermore, we highlight applications of genome design in gene expression, genome structure, genome function, and biocontainment, and discuss the potential of artificial intelligence (AI) in genome design.

4.
J Bone Miner Res ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39303104

RESUMEN

The craniofacial bone, crucial for protecting brain tissue and supporting facial structure, undergoes continuous remodeling through mesenchymal (MSCs) or skeletal stem cells (SSCs) in their niches. Gli1 is an ideal marker for labeling MSCs and osteoprogenitors in this region, and Gli1-lineage cells are identified as pivotal for bone growth, development, repair, and regeneration. Despite its significance, the distribution of Gli1-lineage cells across the dental, oral, and craniofacial (DOC) regions remains to be systematically explored. Utilizing tissue-clearing and light sheet fluorescence microscopy (LSFM) with a Gli1CreER; tdTomatoAi14 mouse model, we mapped the spatial distribution of Gli1-lineage cells throughout the skull, focusing on calvarial bones, sutures, bone marrow, teeth, periodontium, jaw bones, and the temporomandibular joint (TMJ). We found Gli1-lineage cells widespread in these areas, underscoring their significance in DOC regions. Additionally, we observed their role in repairing calvarial bone defects, providing novel insights into craniofacial biology and stem cell niches and enhancing our understanding of stem cells and their progeny's behavior in vivo.


This study investigates the presence and role of a specific stem cell population, known as Gli1-lineage cells, in various parts of the skull and facial bones. Using advanced imaging techniques, we found that these cells are widely distributed across the dental, oral, and craniofacial regions, especially in the cranial sutures, teeth, and jaw. Notably, Gli1-lineage cells migrate to the injury site, which is essential in bone repair and regeneration. These findings enhance our understanding of how stem cells contribute to healing and development in the craniofacial region.

5.
Bioresour Technol ; 413: 131512, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39307473

RESUMEN

The implementation of environmentally friendly and sustainable remediation strategies positively impacts solid waste management. In this study, the Kocuria marina H-2 and Pseudomonas putida B6-2 co-culture system demonstrated enhanced naphthalene biodegradation efficiency compared to single-strain cultures. Under optimal conditions of 35 °C, 200 rpm/min, and a 1:1 ratio of the co-culture system, the naphthalene biodegradation potential was further increased. Notably, the addition of both ethylenediamine-pretreated lignin and p-hydroxybenzoic acid significantly elevated naphthalene degradation rates to 68.5 %. In addition, the oil-liquid surface tension decreased, while cell surface hydrophobicity and colony-forming units increased with the addition of lignin-derived compounds. The modification of naphthalene bioavailability by ethylenediamine-pretreated lignin would accelerate the uptake and transport of hydrocarbons via ABC transporters and flagellar assembly. Importantly, genes related to bacterial chemotaxis and fatty acid biosynthesis were upregulated during the co-metabolism of naphthalene and p-hydroxybenzoic acid, further enhancing naphthalene bioconversion.

6.
Brief Bioinform ; 25(5)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39073829

RESUMEN

With the exponential growth of digital data, there is a pressing need for innovative storage media and techniques. DNA molecules, due to their stability, storage capacity, and density, offer a promising solution for information storage. However, DNA storage also faces numerous challenges, such as complex biochemical constraints and encoding efficiency. This paper presents Explorer, a high-efficiency DNA coding algorithm based on the De Bruijn graph, which leverages its capability to characterize local sequences. Explorer enables coding under various biochemical constraints, such as homopolymers, GC content, and undesired motifs. This paper also introduces Codeformer, a fast decoding algorithm based on the transformer architecture, to further enhance decoding efficiency. Numerical experiments indicate that, compared with other advanced algorithms, Explorer not only achieves stable encoding and decoding under various biochemical constraints but also increases the encoding efficiency and bit rate by ¿10%. Additionally, Codeformer demonstrates the ability to efficiently decode large quantities of DNA sequences. Under different parameter settings, its decoding efficiency exceeds that of traditional algorithms by more than two-fold. When Codeformer is combined with Reed-Solomon code, its decoding accuracy exceeds 99%, making it a good choice for high-speed decoding applications. These advancements are expected to contribute to the development of DNA-based data storage systems and the broader exploration of DNA as a novel information storage medium.


Asunto(s)
Algoritmos , ADN , ADN/genética , ADN/química , Programas Informáticos , Análisis de Secuencia de ADN/métodos , Biología Computacional/métodos
7.
Int J Biol Macromol ; 275(Pt 1): 133650, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38971288

RESUMEN

Consumers are more inclined to choose beef with a high intramuscular fat content (IMF), which regulated by lots of factors. It is very significant to find a miRNA that plays a key role in the accumulation of IMF. In our study, we found that bta-miR-330 was highly expressed in Japanese black cattle and differentially expressed at intramuscular pre-adipocytes differentiation processes. Furthermore, we transfected the bta-miR-330 mimic & inhibitor in intramuscular pre-adipocytes. The results showed that bta-miR-330 inhibits the proliferation but promotes the adipogenesis of intramuscular pre-adipocytes. Subsequently, our study showed that bta-miR-330 binds to SESN3, which inhibits the adipogenesis of intramuscular pre-adipocytes. Moreover, we established the mechanism that bta-miR-330 promotes the adipogenesis of intramuscular pre-adipocytes by targeting SESN3 to activate the Akt-mTOR signaling pathway. Overall, our results revealed that bta-miR-330-SESN3-Akt-mTOR axis plays an important role in adipogenesis of intramuscular pre-adipocytes, which provides a molecular basis for increasing IMF content in beef cattle.


Asunto(s)
Adipocitos , Adipogénesis , MicroARNs , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Serina-Treonina Quinasas TOR , Animales , MicroARNs/genética , MicroARNs/metabolismo , Bovinos , Adipogénesis/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Adipocitos/metabolismo , Adipocitos/citología , Diferenciación Celular , Proliferación Celular
9.
J Agric Food Chem ; 72(22): 12685-12695, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38771136

RESUMEN

Halogenation plays a unique role in the design of agrochemicals. Enzymatic halogenation reactions have attracted great attention due to their excellent specificity and mild reaction conditions. S-adenosyl-l-methionine (SAM)-dependent halogenases mediate the nucleophilic attack of halide ions (X-) to SAM to produce 5'-XDA. However, only 11 SAM-dependent fluorinases and 3 chlorinases have been reported, highlighting the desire for additional halogenases. SAM-dependent hydroxide adenosyltransferase (HATase) has a similar reaction mechanism as halogenases but uses water as a substrate instead of halide ions. Here, we explored a HATase from the thermophile Thermotoga maritima MSB8 and transformed it into a halogenase. We identified a key dyad W8L/V71T for the halogenation reaction. We also obtained the best performing mutants for each halogenation reaction: M1, M2 and M4 for Cl-, Br- and I-, respectively. The M4 mutant retained the thermostability of HATase in the iodination reaction at 80 °C, which surpasses the natural halogenase SalL. QM/MM revealed that these mutants bind halide ions with more suitable angles for nucleophilic attack of C5' of SAM, thus conferring halogenation capabilities. Our work achieved the halide ion specificity of halogenases and generated thermostable halogenases for the first time, which provides new opportunities to expand the halogenase repertoire from hydroxylase.


Asunto(s)
Proteínas Bacterianas , Thermotoga maritima , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Thermotoga maritima/enzimología , Thermotoga maritima/genética , Thermotoga maritima/química , Halogenación , Especificidad por Sustrato , S-Adenosilmetionina/metabolismo , S-Adenosilmetionina/química , Oxidorreductasas/química , Oxidorreductasas/metabolismo , Oxidorreductasas/genética , Biocatálisis
10.
Anim Biotechnol ; 35(1): 2345238, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38775564

RESUMEN

Tropomyosin 3 (TPM3) plays a significant role as a regulatory protein in muscle contraction, affecting the growth and development of skeletal muscles. Despite its importance, limited research has been conducted to investigate the influence of TPM3 on bovine skeletal muscle development. Therefore, this study revealed the role of TPM3 in bovine myoblast growth and development. This research involved conducting a thorough examination of the Qinchuan cattle TPM3 gene using bioinformatics tools to examine its sequence and structural characteristics. Furthermore, TPM3 expression was evaluated in various bovine tissues and cells using quantitative real-time polymerase chain reaction (qRT-PCR). The results showed that the coding region of TPM3 spans 855 bp, with the 161st base being the T base, encoding a protein with 284 amino acids and 19 phosphorylation sites. This protein demonstrated high conservation across species while displaying a predominant α-helix secondary structure despite being an unstable acidic protein. Notably, a noticeable increase in TPM3 expression was observed in the longissimus dorsi muscle and myocardium of calves and adult cattle. Expression patterns varied during different stages of myoblast differentiation. Functional studies that involved interference with TPM3 in Qinchuan cattle myoblasts revealed a very significantly decrease in S-phase cell numbers and EdU-positive staining (P < 0.01), and disrupted myotube morphology. Moreover, interference with TPM3 resulted in significantly (P < 0.05) or highly significantly (P < 0.01) decreased mRNA and protein levels of key proliferation and differentiation markers, indicating its role in the modulation of myoblast behavior. These findings suggest that TPM3 plays an essential role in bovine skeletal muscle growth by influencing myoblast proliferation and differentiation. This study provides a foundation for further exploration into the mechanisms underlying TPM3-mediated regulation of bovine muscle development and provides valuable insights that could guide future research directions as well as potential applications for livestock breeding and addressing muscle-related disorders.


Asunto(s)
Diferenciación Celular , Proliferación Celular , Clonación Molecular , Mioblastos , Tropomiosina , Animales , Bovinos/genética , Tropomiosina/genética , Tropomiosina/metabolismo , Tropomiosina/química , Diferenciación Celular/genética , Mioblastos/metabolismo , Mioblastos/citología , Músculo Esquelético , Secuencia de Aminoácidos , Desarrollo de Músculos/genética
11.
Anal Chem ; 96(12): 5046-5055, 2024 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-38488055

RESUMEN

Bimodal-type multiplexed immunoassays with complementary mode-based correlation analysis are gaining increasing attention for enhancing the practicability of the lateral flow immunoassay (LFIA). Nonetheless, the restriction in visually indistinguishable multitargets induced by a single fluorescent color and difficulty in single acceptor ineffectual fluorescence quenching due to the various spectra of multiple different donors impede the further execution of colorimetric-fluorescence bimodal-type multiplexed LFIAs. Herein, the precise spectral overlap-based donor-acceptor pair construction strategy is proposed by regulating the size of the nanocore, coating it with an appropriate nanoshell, and selecting a suitable fluorescence donor with distinct colors. By in situ coating Prussian blue nanoparticles (PBNPs) on AuNPs with a tunable size and absorption spectrum, the resultant APNPs demonstrate efficient fluorescence quenching ability, higher colloidal stability, remarkable colorimetric intensity, and an enhanced antibody coupling efficiency, all of which facilitate highly sensitive bimodal-type LFIA analysis. Following integration with competitive-type immunoreaction, this precise spectral overlap-supported spatial separation traffic light-typed colorimetric-fluorescence dual-response assay (coined as the STCFD assay) with the limits of detection of 0.013 and 0.152 ng mL-1 for ractopamine and clenbuterol, respectively, was proposed. This work illustrates the superiority of the rational design of a precise spectral overlap-based donor-acceptor pair, hinting at the enormous potential of the STCFD assay in the point-of-care field.


Asunto(s)
Clenbuterol , Nanopartículas del Metal , Oro , Inmunoensayo , Fenómenos Químicos , Límite de Detección
12.
Gut Microbes ; 16(1): 2316575, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38381494

RESUMEN

Intestinal microbiota dysbiosis and metabolic disruption are considered essential characteristics in inflammatory bowel disorders (IBD). Reasonable butyrate supplementation can help patients regulate intestinal flora structure and promote mucosal repair. Here, to restore microbiota homeostasis and butyrate levels in the patient's intestines, we modified the genome of Saccharomyces cerevisiae to produce butyrate. We precisely regulated the relevant metabolic pathways to enable the yeast to produce sufficient butyrate in the intestine with uneven oxygen distribution. A series of engineered strains with different butyrate synthesis abilities was constructed to meet the needs of different patients, and the strongest can reach 1.8 g/L title of butyrate. Next, this series of strains was used to co-cultivate with gut microbiota collected from patients with mild-to-moderate ulcerative colitis. After receiving treatment with engineered strains, the gut microbiota and the butyrate content have been regulated to varying degrees depending on the synthetic ability of the strain. The abundance of probiotics such as Bifidobacterium and Lactobacillus increased, while the abundance of harmful bacteria like Candidatus Bacilloplasma decreased. Meanwhile, the series of butyrate-producing yeast significantly improved trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice by restoring butyrate content. Among the series of engineered yeasts, the strain with the second-highest butyrate synthesis ability showed the most significant regulatory and the best therapeutic effect on the gut microbiota from IBD patients and the colitis mouse model. This study confirmed the existence of a therapeutic window for IBD treatment by supplementing butyrate, and it is necessary to restore butyrate levels according to the actual situation of patients to restore intestinal flora.


Asunto(s)
Colitis , Microbioma Gastrointestinal , Enfermedades Inflamatorias del Intestino , Humanos , Animales , Ratones , Saccharomyces cerevisiae/genética , Butiratos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Disbiosis , Suplementos Dietéticos
13.
ACS Appl Mater Interfaces ; 16(8): 9890-9899, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38353672

RESUMEN

CRISPR/Cas12a-based biosensing is advancing rapidly; however, achieving sensitive and cost-effective reporting of Cas12a activation remains a challenge. In response, we have developed a label-free system capable of postamplifying Cas12a activation by integrating hybridization chain reaction (HCR) and DNA-copper nanoclusters (DNA-CuNCs). The trans-cleavage of Cas12a triggers a silenced HCR, leading to the in situ assembly of fluorescent DNA-CuNCs, allowing for the turn-on reporting of Cas12a activation. Without preamplification, this assay can detect DNA with a detection limit of 5 fM. Furthermore, when coupled with preamplification, the system achieves exceptional sensitivity, detecting the monkeypox virus (MPXV) plasmid at 1 copy in human serum. In a MPXV pseudovirus-based validation test, the obtained results are in agreement with those obtained by qPCR, reinforcing the robustness of this method. Our study represents the first effort to manipulate DNA-CuNC formation on HCR for highly sensitive and cost-effective reporting of Cas12a, resulting in an efficient synthetic biology-enabled sensing platform for biosafety applications.


Asunto(s)
Técnicas Biosensibles , Ácidos Nucleicos , Humanos , Sistemas CRISPR-Cas/genética , Hibridación de Ácido Nucleico , Bioensayo , Colorantes , Cobre , ADN
14.
Anal Chem ; 96(9): 3970-3978, 2024 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-38386411

RESUMEN

Heparin is a highly sulfated linear glycosaminoglycan that is used as an anticoagulant to prevent and treat thrombotic diseases. Herein, we find that heparin specifically inhibits the activation of the Cas12 protein through the competitive binding of heparin and crRNA to Cas12. Studies illustrate that heparin's high molecular weight and strong negative charge are critical parameters for its inhibitory effect. This unexpected finding was engineered for the detection of heparin, affording a low detection limit of 0.36 ng/mL for fluorometric quantification. We further developed a rapid lateral flow-based system named HepaStrip (heparin strip), allowing heparin monitoring in clinical samples within 20 min. Finally, in vivo investigations revealed that heparin can regulate gene editing with the clusters of the regularly spaced short palindromic repeat (CRISPR)/Cas12 system in Escherichia coli. Heparin blocks the formation of Cas12-crRNA ribonucleoprotein, allowing the application of CRISPR for rapid and field-deployable detection of heparin and unleashing the potential use of heparin in future anti-CRISPR applications.


Asunto(s)
Edición Génica , Heparina , Heparina/química , ARN Guía de Sistemas CRISPR-Cas , Sistemas CRISPR-Cas/genética , Anticoagulantes/farmacología , Escherichia coli/metabolismo
15.
Crit Rev Biotechnol ; 44(7): 1439-1459, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38246753

RESUMEN

Stress tolerance is a vital attribute for all living beings to cope with environmental adversities. IrrE (also named PprI) from Deinococcus radiodurans enhances resistance to extreme radiation stress by functioning as a global regulator, mediating the transcription of genes involved in deoxyribonucleic acid (DNA) damage response (DDR). The expression of IrrE augmented the resilience of various species to heat, radiation, oxidation, osmotic stresses and inhibitors, encompassing bacterial, fungal, plant, and mammalian cells. Moreover, IrrE was employed in a global regulator engineering strategy to broaden its applications in stress tolerance. The regulatory impacts of heterologously expressed IrrE have been investigated at the molecular and systems level, including the regulation of genes, proteins, modules, or pathways involved in DNA repair, detoxification proteins, protective molecules, native regulators and other aspects. In this review, we discuss the regulatory role and mechanism of IrrE in the antiradiation response of D. radiodurans. Furthermore, the applications and regulatory effects of heterologous expression of IrrE to enhance abiotic stress tolerance are summarized in particular.


Asunto(s)
Proteínas Bacterianas , Deinococcus , Estrés Fisiológico , Deinococcus/genética , Deinococcus/efectos de la radiación , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Daño del ADN
16.
Anal Chim Acta ; 1288: 342044, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38220315

RESUMEN

Cell surface glycans (CSGs) are essential for cell recognition, adhesion, and invasion, and they also serve as disease biomarkers. Traditional CSG recognition using lectins has limitations such as limited specificity, low stability, high cytotoxicity, and multivalent binding. Aptamers, known for their specific binding capacity to target molecules, are increasingly being employed in the biosensing of CSGs. Aptamers offer the advantage of high flexibility, small size, straightforward modification, and monovalent recognition, enabling their integration into the profiling of CSGs on living cells. In this review, we summarize representative examples of aptamer-based CSG biosensing and identify two strategies for harnessing aptamers in CSG detection: direct recognition based on aptamer-CSG binding and indirect recognition through protein localization. These strategies enable the generation of diverse signals including fluorescence, electrochemical, photoacoustic, and electrochemiluminescence signals for CSG detection. The advantages, challenges, and future perspectives of using aptamers for CSG biosensing are also discussed.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Aptámeros de Nucleótidos/química , Membrana Celular/metabolismo
17.
Environ Sci Technol ; 58(4): 2153-2161, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38244211

RESUMEN

Nitrous oxide (N2O) has a detrimental impact on the greenhouse effect, and its efficient catalytic decomposition at low temperatures remains challenging. Herein, the cobalt-based high-entropy oxide with a spinel-type structure (Co-HEO) is successfully fabricated via a facile coprecipitation method for N2O catalytic decomposition. The obtained Co-HEO catalyst displays more remarkable catalytic performance and higher thermal stability compared with single and binary Co-based oxides, as the temperature of 90% N2O decomposition (T90) is 356 °C. A series of characterization results reveal that the synergistic effect of multiple elements enhances the reducibility and augments oxygen vacancy in the high-entropy system, thus boosting the activity of the Co-HEO catalyst. Moreover, density functional theory (DFT) calculations and the temperature-programmed surface reaction (TPSR) with isotope labeling demonstrate that N2O decomposition on the Co-HEO catalyst follows the Langmuir-Hinshelwood (L-H) mechanism with the promotion of abundant oxygen vacancies. This work provides a fundamental understanding of the synergistic catalytic effect in N2O decomposition and paves the way for the novel environmental catalytic applications of HEO.


Asunto(s)
Cobalto , Óxidos , Entropía , Óxidos/química , Cobalto/química , Oxígeno
18.
J Agric Food Chem ; 72(2): 1203-1212, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38179953

RESUMEN

Organofluorine compounds have attracted substantial attention owing to their wide application in agrochemistry. Fluorinase (FlA) is a unique enzyme in nature that can incorporate fluorine into an organic molecule. Chlorinase (SalL) has a similar mechanism as fluorinase and can use chloride but not fluoride as a substrate to generate 5'-chloro-deoxyadenosine (5'-ClDA) from S-adenosyl-l-methionine (SAM). Therefore, identifying the features that lead to this selectivity for halide ions is highly important. Here, we engineered SalL to gain the function of FlA. We found that residue Tyr70 plays a key role in this conversion through alanine scanning. Site-saturation mutagenesis experiments demonstrated that Y70A/C/S/T/G all exhibited obvious fluorinase activity. The G131S mutant of SalL, in which the previously thought crucial residue Ser158 for fluoride binding in FlA was introduced, did not exhibit fluorination activity. Compared with the Y70T single mutant, the double mutant Y70T/W129F increased 5'-fluoro-5-deoxyadenosine (5'-FDA) production by 76%. The quantum mechanics (QM)/molecular mechanics (MM) calculations suggested that the lower energy barriers and shorter nucleophilic distance from F- to SAM in the mutants than in the SalL wild-type may contribute to the activity. Therefore, our study not only renders SalL the activity of FlA but also sheds light on the enzyme selectivity between fluoride versus chloride.


Asunto(s)
Cloruros , Fluoruros , Fluoruros/química , Oxidorreductasas/metabolismo , Proteínas Bacterianas/metabolismo , Desoxiadenosinas , S-Adenosilmetionina/metabolismo
19.
Biotechnol Adv ; 70: 108274, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37913947

RESUMEN

Bioconversion of bioresources/wastes (e.g., lignin, chemical pulping byproducts) represents a promising approach for developing a bioeconomy to help address growing energy and materials demands. Rhodococcus, a promising microbial strain, utilizes numerous carbon sources to produce lipids, which are precursors for synthesizing biodiesel and aviation fuels. However, compared to chemical conversion, bioconversion involves living cells, which is a more complex system that needs further understanding and upgrading. Various wastes amenable to bioconversion are reviewed herein to highlight the potential of Rhodococci for producing lipid-derived bioproducts. In light of the abundant availability of these substrates, Rhodococcus' metabolic pathways converting them to lipids are analyzed from a "beginning-to-end" view. Based on an in-depth understanding of microbial metabolic routes, genetic modifications of Rhodococcus by employing emerging tools (e.g., multiplex genome editing, biosensors, and genome-scale metabolic models) are presented for promoting the bioconversion. Co-solvent enhanced lignocellulose fractionation (CELF) strategy facilitates the generation of a lignin-derived aromatic stream suitable for the Rhodococcus' utilization. Novel alkali sterilization (AS) and elimination of thermal sterilization (ETS) approaches can significantly enhance the bioaccessibility of lignin and its derived aromatics in aqueous fermentation media, which promotes lipid titer significantly. In order to achieve value-added utilization of lignin, biodiesel and aviation fuel synthesis from lignin and lipids are further discussed. The possible directions for unleashing the capacity of Rhodococcus through synergistically modifying microbial strains, substrates, and fermentation processes are proposed toward a sustainable biological lignin valorization.


Asunto(s)
Lignina , Rhodococcus , Lignina/metabolismo , Rhodococcus/genética , Rhodococcus/metabolismo , Biocombustibles , Fermentación , Lípidos , Biomasa
20.
Trends Biotechnol ; 42(1): 14-16, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37482468

RESUMEN

Therapeutics based on clustered regularly interspaced short palindromic repeats (CRISPR) have gained significant attention as a promising synthetic biology technique, but there are concerns about the potential for persistent activation of CRISPR-associated protein (Cas) and subsequent off-target effects. This forum focuses on advances in anti-CRISPR studies based on non-protein substances in the hope of developing effective anti-CRISPR strategies to mitigate these concerns.


Asunto(s)
Proteínas Asociadas a CRISPR , Sistemas CRISPR-Cas , Proteínas Asociadas a CRISPR/antagonistas & inhibidores
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