Escherichia coli

大肠杆菌
  • 文章类型: Journal Article
    生物仿制药是从活生物体产生的或含有活成分的生物药物。它们具有相同的氨基酸序列和免疫原性。这些药物被认为是具有成本效益的,并且用于治疗癌症和其他内分泌紊乱。生物仿制药的主要目的是预测生物相似性,功效,和治疗费用;它们已获得食品和药物管理局(FDA)的批准,没有临床意义。它们涉及分析研究,以了解相似性和差异性。一家生物仿制药制造商建立了FDA批准的参考产品来评估生物相似性。下一代测序的贡献正在演变为研究器官肿瘤及其进展,其对癌症患者有影响力的治疗方法,以展示和靶向罕见突变。这项研究将有助于了解生物仿制药在胃肠道疾病中的未来前景,结直肠癌,和甲状腺癌。它们还有助于在临床实践中通过血液和液体活检靶向具有基本突变类别和药物原型的特定器官,细胞治疗,基因治疗,重组治疗性蛋白质,和个性化的药物。生物类似物衍生物如单克隆抗体如曲妥珠单抗和利妥昔单抗是用于癌症治疗的常见药物。大肠杆菌产生超过六种抗体或抗体衍生的蛋白质来治疗癌症,例如非格司亭,epoetinalfa,等等。
    Biosimilars are biological drugs created from living organisms or that contain living components. They share an identical amino-acid sequence and immunogenicity. These drugs are considered to be cost-effective and are utilized in the treatment of cancer and other endocrine disorders. The primary aim of biosimilars is to predict biosimilarity, efficacy, and treatment costs; they are approved by the Food and Drug Administration (FDA) and have no clinical implications. They involve analytical studies to understand the similarities and dissimilarities. A biosimilar manufacturer sets up FDA-approved reference products to evaluate biosimilarity. The contribution of next-generation sequencing is evolving to study the organ tumor and its progression with its impactful therapeutic approach on cancer patients to showcase and target rare mutations. The study shall help to understand the future perspectives of biosimilars for use in gastro-entero-logic diseases, colorectal cancer, and thyroid cancer. They also help target specific organs with essential mutational categories and drug prototypes in clinical practices with blood and liquid biopsy, cell treatment, gene therapy, recombinant therapeutic proteins, and personalized medications. Biosimilar derivatives such as monoclonal antibodies like trastuzumab and rituximab are common drugs used in cancer therapy. Escherichia coli produces more than six antibodies or antibody-derived proteins to treat cancer such as filgrastim, epoetin alfa, and so on.
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  • 文章类型: Journal Article
    复方新诺明,磺胺甲恶唑和甲氧苄啶的联合制剂,是几种传染病的首选治疗方法之一,尤其是尿路感染。复方新诺明的两种成分都是合成抗菌药物,他们的组合在大约半个世纪前被引入医学治疗学。在革兰氏阴性细菌中,对复方新诺明的耐药性很普遍,基于从辅助基因组中获得赋予其每个抗菌成分抗性的基因。从先前对一组耐复方新诺明的尿路致病性大肠杆菌菌株中对磺胺甲恶唑的抗性基因型的认识出发,这项工作的重点是鉴定这些相同菌株的甲氧苄啶抗性的遗传基础。采用的分子技术包括特定扩增子的PCR和Sanger测序,转移质粒的缀合实验和NGS测序。鉴定了赋予甲氧苄啶抗性表型的可移动遗传元件,并包括整合子,转座子和单基因盒。因此,菌株表现出几种联合抵抗两种抗生素的方法,暗示赋予对磺胺甲恶唑(sul)和甲氧苄啶(dfra)抗性的基因之间的遗传连锁水平不同。两个结构特别有趣,因为它们代表了确保耐复方新诺明的高度内聚排列。他们都携带了一个基因盒,dfrA14或dfrA1,集成在保守簇sul2-strA-strB的两个不同点中,进行可转移的质粒。结果表明,复方新诺明对我们环境中的细菌施加的压力仍在促进向日益紧密的基因排列进化,由可移动的遗传因子携带,这些遗传因子在基因组中移动,并在细菌之间水平转移。
    Cotrimoxazole, the combined formulation of sulfamethoxazole and trimethoprim, is one of the treatments of choice for several infectious diseases, particularly urinary tract infections. Both components of cotrimoxazole are synthetic antimicrobial drugs, and their combination was introduced into medical therapeutics about half a century ago. In Gram-negative bacteria, resistance to cotrimoxazole is widespread, being based on the acquisition of genes from the auxiliary genome that confer resistance to each of its antibacterial components. Starting from previous knowledge on the genotype of resistance to sulfamethoxazole in a collection of cotrimoxazole resistant uropathogenic Escherichia coli strains, this work focused on the identification of the genetic bases of the trimethoprim resistance of these same strains. Molecular techniques employed included PCR and Sanger sequencing of specific amplicons, conjugation experiments and NGS sequencing of the transferred plasmids. Mobile genetic elements conferring the trimethoprim resistance phenotype were identified and included integrons, transposons and single gene cassettes. Therefore, strains exhibited several ways to jointly resist both antibiotics, implying different levels of genetic linkage between genes conferring resistance to sulfamethoxazole (sul) and trimethoprim (dfrA). Two structures were particularly interesting because they represented a highly cohesive arrangements ensuring cotrimoxazole resistance. They both carried a single gene cassette, dfrA14 or dfrA1, integrated in two different points of a conserved cluster sul2-strA-strB, carried on transferable plasmids. The results suggest that the pressure exerted by cotrimoxazole on bacteria of our environment is still promoting the evolution toward increasingly compact gene arrangements, carried by mobile genetic elements that move them in the genome and also transfer them horizontally among bacteria.
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  • 文章类型: Journal Article
    鸟分枝杆菌亚种副结核(MAP)是约翰氏病的病原体,反刍动物的慢性肉芽肿性肠炎。MAP通过小肠在宿主中建立感染。这需要细菌粘附,并被内化,肠道细胞。为此目的由MAP表达的效应分子仍有待完全鉴定和理解。哺乳动物细胞进入(mce)蛋白已被证明能够使其他分枝杆菌物种附着并侵入宿主上皮细胞。这里,我们表达了Mce1A,Mce1D,来自非侵入性大肠杆菌表面的MAP的Mce3C和Mce4A蛋白表征了它们在MAP与宿主之间的初始相互作用中的作用。为此,发现mce1A的表达显着增加大肠杆菌在人单核细胞样THP-1细胞中附着和细胞内存活的能力,而mce1D的表达被发现显着增加大肠杆菌对牛上皮细胞样MDBK细胞的附着和侵袭,暗示细胞类型特异性。此外,Mce1A和Mce1D在先前非侵入性大肠杆菌表面上的表达增强了细菌感染3D牛基础出肠的能力。一起,我们的数据有助于我们理解MAP在与宿主的初始相互作用中使用的效应分子,并可能为治疗干预提供潜在的靶点。
    Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of Johne\'s Disease, a chronic granulomatous enteritis of ruminants. MAP establishes an infection in the host via the small intestine. This requires the bacterium to adhere to, and be internalised by, cells of the intestinal tract. The effector molecules expressed by MAP for this purpose remain to be fully identified and understood. Mammalian cell entry (mce) proteins have been shown to enable other Mycobacterial species to attach to and invade host epithelial cells. Here, we have expressed Mce1A, Mce1D, Mce3C and Mce4A proteins derived from MAP on the surface of a non-invasive Escherichia coli to characterise their role in the initial interaction between MAP and the host. To this end, expression of mce1A was found to significantly increase the ability of the E. coli to attach and survive intracellularly in human monocyte-like THP-1 cells, whereas expression of mce1D was found to significantly increase attachment and invasion of E. coli to bovine epithelial cell-like MDBK cells, implying cell-type specificity. Furthermore, expression of Mce1A and Mce1D on the surface of a previously non-invasive E. coli enhanced the ability of the bacterium to infect 3D bovine basal-out enteroids. Together, our data contributes to our understanding of the effector molecules utilised by MAP in the initial interaction with the host, and may provide potential targets for therapeutic intervention.
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  • 文章类型: Journal Article
    肠聚集性大肠杆菌(EAEC)是世界范围内腹泻的主要原因。EAEC高度粘附于培养的上皮细胞并产生生物膜。粘附和生物膜形成都依赖于聚集粘附菌毛(AAF)的存在。我们比较了五种AAF类型中每一种的两种EAEC菌株的生物膜形成。我们发现AAF类型与产生的生物膜水平无关。由于EAEC生物膜的组成尚未完全描述,我们对EAEC生物膜进行染色以确定它们是否含有蛋白质,碳水化合物糖蛋白,和/或eDNA,发现EAEC生物膜包含所有三种细胞外成分。接下来,我们评估了蛋白酶K处理介导的生长或成熟的EAEC生物膜的变化,DNase,或碳水化合物裂解剂靶向基质的不同组分。对于超过一半的测试菌株,用蛋白酶K处理的生长生物膜降低了生物膜染色。相比之下,尽管偏高碘酸钠仅以定量方式改变了两个菌株的生物膜,用偏高碘酸钠处理的生物膜图像显示EAEC更分散。总的来说,我们发现EAEC菌株对治疗反应的变异性,没有一种治疗方法对所有菌株产生生物膜变化。最后,一旦形成,成熟的EAEC生物膜比在那些相同处理存在下生长的生物膜对处理更具抗性。
    Enteroaggregative E. coli (EAEC) is a major cause of diarrhea worldwide. EAEC are highly adherent to cultured epithelial cells and make biofilms. Both adherence and biofilm formation rely on the presence of aggregative adherence fimbriae (AAF). We compared biofilm formation from two EAEC strains of each of the five AAF types. We found that AAF type did not correlate with the level of biofilm produced. Because the composition of the EAEC biofilm has not been fully described, we stained EAEC biofilms to determine if they contained protein, carbohydrate glycoproteins, and/or eDNA and found that EAEC biofilms contained all three extracellular components. Next, we assessed the changes to the growing or mature EAEC biofilm mediated by treatment with proteinase K, DNase, or a carbohydrate cleavage agent to target the different components of the matrix. Growing biofilms treated with proteinase K had decreased biofilm staining for more than half of the strains tested. In contrast, although sodium metaperiodate only altered the biofilm in a quantitative way for two strains, images of biofilms treated with sodium metaperiodate showed that the EAEC were more spread out. Overall, we found variability in the response of the EAEC strains to the treatments, with no one treatment producing a biofilm change for all strains. Finally, once formed, mature EAEC biofilms were more resistant to treatment than biofilms grown in the presence of those same treatments.
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  • 文章类型: Journal Article
    肽聚糖(PG)囊围绕细胞质膜,通过承受内部膨胀压力保持细胞的完整性。在细胞生长过程中,PG内肽酶切割完全封闭的囊的交联,允许新的聚糖链的掺入和肽聚糖网的扩展。外膜锚定的NlpI与PG合成复合物附近的水解酶和合酶相关,促进空间接近PG水解。这里,我们提出了与内肽酶MepS复合的衔接子NlpI的结构,揭示NlpI如何招募多个MepS分子并随后影响PG扩展的原子细节。NlpI结合在MepS的固有无序N端引发无序到有序的转变,同时促进单体MepS的二聚化。这导致分别位于NlpI的二聚化界面的两个相对侧的两个不对称MepS二聚体的排列,从而增强PG水解中的MepS活性。值得注意的是,MepS的蛋白质水平主要由尾部特异性蛋白酶Prc调节,已知与NlpI相互作用。Prc-NlpI-MepS复合物的结构表明NlpI将MepS和Prc结合在一起,导致Prc有效的MepS降解。总的来说,我们的结果提供了有关Prc对细胞内肽酶的NlpI使能亲合力效应和NlpI指导的MepS降解的结构见解。
    Peptidoglycan (PG) sacculi surround the cytoplasmic membrane, maintaining cell integrity by withstanding internal turgor pressure. During cell growth, PG endopeptidases cleave the crosslinks of the fully closed sacculi, allowing for the incorporation of new glycan strands and expansion of the peptidoglycan mesh. Outer-membrane-anchored NlpI associates with hydrolases and synthases near PG synthesis complexes, facilitating spatially close PG hydrolysis. Here, we present the structure of adaptor NlpI in complex with the endopeptidase MepS, revealing atomic details of how NlpI recruits multiple MepS molecules and subsequently influences PG expansion. NlpI binding elicits a disorder-to-order transition in the intrinsically disordered N-terminal of MepS, concomitantly promoting the dimerization of monomeric MepS. This results in the alignment of two asymmetric MepS dimers respectively located on the two opposite sides of the dimerization interface of NlpI, thus enhancing MepS activity in PG hydrolysis. Notably, the protein level of MepS is primarily modulated by the tail-specific protease Prc, which is known to interact with NlpI. The structure of the Prc-NlpI-MepS complex demonstrates that NlpI brings together MepS and Prc, leading to the efficient MepS degradation by Prc. Collectively, our results provide structural insights into the NlpI-enabled avidity effect of cellular endopeptidases and NlpI-directed MepS degradation by Prc.
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  • 文章类型: Journal Article
    抗菌素耐药性(AMR)是主要的公共卫生威胁,细菌快速传播抗菌药物耐药基因(ARG)的能力加剧了这种情况。由于不相容组P(IncP)的共轭质粒是普遍存在的可移动遗传元件,通常携带ARG并且宿主范围广,它们是防止AMR传播的重要目标。质粒依赖性噬菌体通过将接合分泌系统的成分识别为受体来感染携带质粒的细菌。我们试图使用携带共轭IncP质粒pKJK5的肠沙门氏菌无毒菌株从废水中分离出依赖质粒的噬菌体。无论该网站,我们仅获得了属于Alphatectivirus属的噬菌体。对11个分离株进行了测序,他们的基因组分析,以及使用S.enterica建立的宿主范围,大肠杆菌,和携带不同共轭质粒的恶臭假单胞菌。我们证实,使用依赖培养和不依赖培养的方法,Alphatectivirus在家庭和医院废水中含量丰富。然而,这些结果与它们在宏基因组中的低发生或检测不到不一致.因此,总的来说,我们的结果强调了进行噬菌体分离以揭示多样性的重要性,特别是考虑到质粒依赖性噬菌体减少接合质粒携带的ARG传播的潜力,并帮助对抗AMR危机。
    Antimicrobial resistance (AMR) is a major public health threat, exacerbated by the ability of bacteria to rapidly disseminate antimicrobial resistance genes (ARG). Since conjugative plasmids of the incompatibility group P (IncP) are ubiquitous mobile genetic elements that often carry ARG and are broad-host-range, they are important targets to prevent the dissemination of AMR. Plasmid-dependent phages infect plasmid-carrying bacteria by recognizing components of the conjugative secretion system as receptors. We sought to isolate plasmid-dependent phages from wastewater using an avirulent strain of Salmonella enterica carrying the conjugative IncP plasmid pKJK5. Irrespective of the site, we only obtained bacteriophages belonging to the genus Alphatectivirus. Eleven isolates were sequenced, their genomes analyzed, and their host range established using S. enterica, Escherichia coli, and Pseudomonas putida carrying diverse conjugative plasmids. We confirmed that Alphatectivirus are abundant in domestic and hospital wastewater using culture-dependent and culture-independent approaches. However, these results are not consistent with their low or undetectable occurrence in metagenomes. Therefore, overall, our results emphasize the importance of performing phage isolation to uncover diversity, especially considering the potential of plasmid-dependent phages to reduce the spread of ARG carried by conjugative plasmids, and to help combat the AMR crisis.
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  • 文章类型: Journal Article
    推断基因调控网络(GRN)是系统生物学的重要挑战之一。和许多优秀的计算方法已经被提出;然而,仍然存在一些挑战,特别是在真实的数据集。在这项研究中,我们提出了基于有向图卷积神经网络的GRN推断方法(DGCGRN)。为了更好地理解和处理GRN的有向图结构数据,进行了有向图卷积神经网络,在保留有向图结构信息的同时,还充分利用了邻居节点特征。图神经网络采用局部增广策略解决了GRN中大量低度节点导致预测精度差的问题。此外,对于像大肠杆菌这样的真实数据,利用Bi-GRU提取隐藏特征,计算基因序列的统计理化特征,得到序列特征。在训练阶段,采用动态更新策略,将得到的边预测分数转换为边权重,指导模型后续的训练过程。在合成基准数据集和真实数据集上的结果表明,DGCGRN的预测性能明显优于现有模型。此外,膀胱尿路上皮癌和肺癌细胞的案例研究也说明了所提出模型的性能。
    Inferring gene regulatory network (GRN) is one of the important challenges in systems biology, and many outstanding computational methods have been proposed; however there remains some challenges especially in real datasets. In this study, we propose Directed Graph Convolutional neural network-based method for GRN inference (DGCGRN). To better understand and process the directed graph structure data of GRN, a directed graph convolutional neural network is conducted which retains the structural information of the directed graph while also making full use of neighbor node features. The local augmentation strategy is adopted in graph neural network to solve the problem of poor prediction accuracy caused by a large number of low-degree nodes in GRN. In addition, for real data such as E.coli, sequence features are obtained by extracting hidden features using Bi-GRU and calculating the statistical physicochemical characteristics of gene sequence. At the training stage, a dynamic update strategy is used to convert the obtained edge prediction scores into edge weights to guide the subsequent training process of the model. The results on synthetic benchmark datasets and real datasets show that the prediction performance of DGCGRN is significantly better than existing models. Furthermore, the case studies on bladder uroepithelial carcinoma and lung cancer cells also illustrate the performance of the proposed model.
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  • 文章类型: Journal Article
    抗菌素耐药性正日益成为全球健康问题。本研究旨在调查和报道MDR大肠杆菌(E.大肠杆菌)患病率,阻力,和乔斯家禽的毒力基因,高原州,尼日利亚。
    使用微生物标准方法和聚合酶链反应(PCR)分析样品。
    从本地和外来家禽品种中总共收集了179个泄殖腔拭子,其中99.4%(178/179)的大肠杆菌检测呈阳性。在这些文化上确定的样本中,99.4%(177/178)是进一步证实的分子量为401bp的大肠杆菌。从确认的分离物中观察到45%(80/178)的多药物抗性。进行PCR测定以检测与抗生素抗性相关的基因,具体来说,四环素(tetA基因),磺酰胺(sul1基因),氨苄青霉素(ampC基因),和喹诺酮(gyrA基因)。抗菌药物敏感性试验(AST)结果显示有相当大的抗生素耐药性,81.9%(145/177)的菌株对四环素耐药,80.2%(142/177)对喹诺酮,69.5%(123/177)对磺酰胺,氨苄青霉素占66.1%(117/177)。使用多重PCR检测eae,对18株对多达4种不同抗生素具有抗性的分离株进行了进一步分析,hlyA,rfbE,FILC,和fstx毒力基因.研究发现,44.4%(15/18)的分离株eae基因阳性,stx为27.7%(5/18),22.2%(4/18)为rfbe基因,和5.5%(1)的hlya基因,而且没有一个基因检测呈阳性.
    这些结果显示高抗生素耐药性,毒力基因,以及家禽大肠杆菌中显著水平的MDR。这项研究强调了在家禽业中迫切需要抗菌管理实践,因为它们对食品安全和公共卫生具有深远的影响。这个问题在尼日利亚尤为关键,家禽养殖构成小农养殖实践的重要部分。
    UNASSIGNED: Antimicrobial resistance is increasingly becoming a global health concern. This study aimed to investigate and report MDR Escherichia coli (E. coli) prevalence, resistance, and virulence genes from poultry in Jos, Plateau State, Nigeria.
    UNASSIGNED: The samples were analyzed using microbiological standard methods and polymerase chain reactions (PCRs).
    UNASSIGNED: A total of 179 cloacal swabs were collected from bothlocal and exotic poultry breeds, of which 99.4% (178/179) tested positive for E. coli. Among these culturally identified samples, 99.4% (177/178) were furtherconfirmed Escherichia coli with a molecular weight of 401 bp. Multidrugresistance of 45% (80/178) was observed from the confirmed isolates. PCR assays were conducted to detect genes associated with resistance to antibiotics, specifically, tetracycline (tetA gene), sulfonamide (sul1 gene), ampicillin (ampC gene), and quinolone (gyrA gene). Antimicrobial susceptibility test (AST) results revealed substantial antibiotic resistance, with 81.9% (145/177) of the isolates being resistant to tetracycline, 80.2% (142/177) to quinolone, 69.5% (123/177) to sulfonamide, and 66.1% (117/177) to ampicillin. Further analysis on 18 isolates that showed resistance to up to four different antibiotics was carried out using multiplex PCR to detect eae, hlyA, rfbE, fliC, and fstx virulence genes. The study found that 44.4% (15/18) of the isolates were positive for the eae gene, 27.7% (5/18) for stx, 22.2% (4/18) for rfbe gene, and 5.5% (1) for hlya gene, and none tested positive for fliC gene.
    UNASSIGNED: These results showed high antibiotic resistance, virulent genes, and significant levels of MDR in E. coli from poultry. This study highlights the urgent need for antimicrobial stewardship practices within the poultry industry due to their profound implications for food safety and public health. This issue is particularly critical in Nigeria, where poultry farming constitutes a significant portion of smallholder farming practices.
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  • 文章类型: Journal Article
    通过水热合成开发了ZnO纳米棒无纺布(ZNRN),以促进预防呼吸道病原体的传播。通过响应面法提高了ZNRN的超疏水性和抗菌性能。合成的材料表现出显著的防水性,水接触角为163.9°,因此对大肠杆菌的抗菌率为91.8%(E.大肠杆菌)和79.75%的金黄色葡萄球菌(S.金黄色葡萄球菌)。这表明具有较薄肽聚糖的大肠杆菌可能比金黄色葡萄球菌更容易被杀死。这项研究确定了合成条件对抗菌效果的显着影响,全面的多变量分析阐明了潜在的相关性。此外,通过SEM和XRD分析对ZNRN的ZnO纳米棒结构进行了表征。它赋予超疏水性(从而防止细菌粘附到ZNRN表面)和抗菌能力(从而通过刺穿这些纳米棒破坏细胞)的性质。因此,希望将两个这样的特征对齐,以帮助支持个人防护设备的开发,这有助于避免呼吸道感染的传播。
    ZnO nanorod nonwoven fabrics (ZNRN) were developed through hydrothermal synthesis to facilitate the prevention of the transmission of respiratory pathogens. The superhydrophobicity and antibacterial properties of ZNRN were improved through the response surface methodology. The synthesized material exhibited significant water repellency, indicated by a water contact angle of 163.9°, and thus demonstrated antibacterial rates of 91.8% for Escherichia coli (E. coli) and 79.75% for Staphylococcus aureus (S. aureus). This indicated that E. coli with thinner peptidoglycan may be more easily killed than S. aureus. This study identified significant effects of synthesis conditions on the antibacterial effectiveness, with comprehensive multivariate analyses elucidating the underlying correlations. In addition, the ZnO nanorod structure of ZNRN was characterized through SEM and XRD analyses. It endows the properties of superhydrophobicity (thus preventing bacteria from adhering to the ZNRN surface) and antibacterial capacity (thus damaging cells through the puncturing of these nanorods). Consequently, the alignment of two such features is desired to help support the development of personal protective equipment, which assists in avoiding the spread of respiratory infections.
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  • 文章类型: Journal Article
    磷酸烯醇丙酮酸-草酰乙酸-丙酮酸衍生的氨基酸(POP-AA)是细胞代谢中的天然中间体,其中磷酸烯醇丙酮酸-草酰乙酸-丙酮酸(POP)节点是大多数生物体中存在的主要代谢途径之间的转换点。POP-AA在营养学中有着广泛的应用,食物,和制药行业。这些氨基酸主要通过微生物发酵在大肠杆菌和谷氨酸棒杆菌中产生。随着市场需求的迅速增加,随着全球粮食短缺的形势,这两种细菌的工业生产能力遇到了两个瓶颈:产品转化效率低和原材料成本高。旨在推动具有更高产量和生产率的工程菌株的更新和升级,本文全面总结了磷酸烯醇丙酮酸-草酰乙酸-丙酮酸节点的代谢工程技术的基本策略,包括L-色氨酸,L-酪氨酸,L-苯丙氨酸,L-缬氨酸,L-赖氨酸,L-苏氨酸,和L-异亮氨酸.应考虑关于POP节点中碳通量再分布和氨基酸形成的新的异源途径和调节方法,以提高POP-AA的产量,使其接近最大理论值。此外,展望了未来低成本原料和能源利用发展氨基酸过剩生产者的战略。
    The phosphoenol pyruvate-oxaloacetate-pyruvate-derived amino acids (POP-AAs) comprise native intermediates in cellular metabolism, within which the phosphoenol pyruvate-oxaloacetate-pyruvate (POP) node is the switch point among the major metabolic pathways existing in most living organisms. POP-AAs have widespread applications in the nutrition, food, and pharmaceutical industries. These amino acids have been predominantly produced in Escherichia coli and Corynebacterium glutamicum through microbial fermentation. With the rapid increase in market requirements, along with the global food shortage situation, the industrial production capacity of these two bacteria has encountered two bottlenecks: low product conversion efficiency and high cost of raw materials. Aiming to push forward the update and upgrade of engineered strains with higher yield and productivity, this paper presents a comprehensive summarization of the fundamental strategy of metabolic engineering techniques around phosphoenol pyruvate-oxaloacetate-pyruvate node for POP-AA production, including L-tryptophan, L-tyrosine, L-phenylalanine, L-valine, L-lysine, L-threonine, and L-isoleucine. Novel heterologous routes and regulation methods regarding the carbon flux redistribution in the POP node and the formation of amino acids should be taken into consideration to improve POP-AA production to approach maximum theoretical values. Furthermore, an outlook for future strategies of low-cost feedstock and energy utilization for developing amino acid overproducers is proposed.
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