scholarly journals Using Plate-Wash PCR and High-Throughput Sequencing to Measure Cultivated Diversity for Natural Product Discovery Efforts

2021 ◽  
Vol 12 ◽  
Author(s):  
Emily N. Junkins ◽  
Bradley S. Stevenson

Molecular techniques continue to reveal a growing disparity between the immense diversity of microbial life and the small proportion that is in pure culture. The disparity, originally dubbed “the great plate count anomaly” by Staley and Konopka, has become even more vexing given our increased understanding of the importance of microbiomes to a host and the role of microorganisms in the vital biogeochemical functions of our biosphere. Searching for novel antimicrobial drug targets often focuses on screening a broad diversity of microorganisms. If diverse microorganisms are to be screened, they need to be cultivated. Recent innovative research has used molecular techniques to assess the efficacy of cultivation efforts, providing invaluable feedback to cultivation strategies for isolating targeted and/or novel microorganisms. Here, we aimed to determine the efficiency of cultivating representative microorganisms from a non-human, mammalian microbiome, identify those microorganisms, and determine the bioactivity of isolates. Sequence-based data indicated that around 57% of the ASVs detected in the original inoculum were cultivated in our experiments, but nearly 53% of the total ASVs that were present in our cultivation experiments were not detected in the original inoculum. In light of our controls, our data suggests that when molecular tools were used to characterize our cultivation efforts, they provided a more complete and more complex, understanding of which organisms were present compared to what was eventually detected during cultivation. Lastly, about 3% of the isolates collected from our cultivation experiments showed inhibitory bioactivity against an already multidrug-resistant pathogen panel, further highlighting the importance of informing and directing future cultivation efforts with molecular tools.

2020 ◽  
Author(s):  
Emily N. Junkins ◽  
Bradley S. Stevenson

AbstractMolecular techniques continue to reveal a growing disparity between the immense diversity of microbial life and the small proportion that is in pure culture. The disparity, originally dubbed “the great plate count anomaly” by Staley and Konopka, has become even more vexing given our increased understanding of the importance of microbiomes to a host and the role of microorganisms in the vital biogeochemical functions of our biosphere. Searching for novel antimicrobial drug targets often focuses on screening a broad diversity of microorganisms. If diverse microorganisms are to be screened, they need to be cultivated. Recent innovative research has used molecular techniques to assess the efficacy of cultivation efforts, providing invaluable feedback to cultivation strategies for isolating targeted and/or novel microorganisms. Here, we aimed to determine the efficiency of cultivating representative microorganisms from a non-human, mammalian microbiome, identify those microorganisms, and determine the bioactivity of isolates. Molecular methods indicated that around 57% of the ASVs detected in the original inoculum were cultivated in our experiments, but nearly 53% of the total ASVs that were present in our cultivation experiments were not detected in the original inoculum. In light of our controls, our data suggests that when molecular tools were used to characterize our cultivation efforts, they provided a more complete, albeit more complex, understanding of which organisms were present compared to what was eventually cultivated. Lastly, about 3% of the isolates collected from our cultivation experiments showed inhibitory bioactivity against a multidrug-resistant pathogen panel, further highlighting the importance of informing and directing future cultivation efforts with molecular tools.ImportanceCultivation is the definitive tool to understand a microorganism’s physiology, metabolism, and ecological role(s). Despite continuous efforts to hone this skill, researchers are still observing yet-to-be cultivated organisms through high-throughput sequencing studies. Here, we use the very same tool that highlights biodiversity to assess cultivation efficiency. When applied to drug discovery, where screening a vast number of isolates for bioactive metabolites is common, cultivating redundant organisms is a hindrance. However, we observed that cultivating in combination with molecular tools can expand the observed diversity of an environment and its community, potentially increasing the number of microorganisms to be screened for natural products.


2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e13045-e13045
Author(s):  
Chang Gong ◽  
Qun Lin ◽  
Xiaolin Fang ◽  
Wenguo Jiang ◽  
Jun Li ◽  
...  

e13045 Background: Compared to lumial breast cancer, the proporation of triple-negative breast cancer (TNBC) with bone metastases (BMs) is relatively low and few data focusing on the mechanism of the BMs in TNBC are available, Here, we screened that CTNND1 was associated with BMs of TNBC by integrating high-throughput sequencing, and further investigated the role of CTNND1 in BMs of TNBC in vitro. Methods: TNBC tissue samples with only BMs (n = 6) and without any metastasis (n = 10) were tested using high-throughput sequencing and 11 differentially expressed relative genes were identified. We then quantified these 11 genes in normal breast tissue samples (n = 26), TNBC tissue samples with only BMs (n = 10), TNBC tissue samples without any metastasis (n = 88) as well as luminal tissue samples with BMs(n = 10)through qPCR and immunohistochemical staining (IHC). The effects of knocking down CTNND1 on the interaction between TNBC cells and osteoblasts were examined by cell adhesion, transwell migration and matrigel invasion assays. To explorethe role of CTNND1 in mediating bone metastasis in TNBC, we used RNA-sequencing to find out the relative downstream gene CXCR4 and PI3K-AKT-mTOR pathway and verified it in vitro by Western Blotting. Results: Combining our high-throughput sequencing data, qPCR and IHC in clinical tissue samples, we verified that CTNND1 was decreased in TNBC patients with bone metastasis compared to normal tissue and luminal tissue with BMs. Knocking down of CTNND1 in TNBC cells including MDA-MB-231, MDA-MB-468 and BT549 weakened cells adhesion, but facilitated cells migration and invasion. Mechanically, knocking down of CTNND1 upregulated CXCR4 via activating PI3K-AKT-mTOR pathway in TNBC but not luminal and HER2- positive breast cancer cells lines. Conclusions: CTNND1 mediates bone metastasis in triple-negative breast cancer via regulating CXCR4.CTNND1 may serve as a potential predictor of bone metastasis for TNBC patients.


2019 ◽  
Vol 109 (5) ◽  
pp. 716-725 ◽  
Author(s):  
D. E. V. Villamor ◽  
T. Ho ◽  
M. Al Rwahnih ◽  
R. R. Martin ◽  
I. E. Tzanetakis

Over the last decade, virologists have discovered an unprecedented number of viruses using high throughput sequencing (HTS), which led to the advancement of our knowledge on the diversity of viruses in nature, particularly unraveling the virome of many agricultural crops. However, these new virus discoveries have often widened the gaps in our understanding of virus biology; the forefront of which is the actual role of a new virus in disease, if any. Yet, when used critically in etiological studies, HTS is a powerful tool to establish disease causality between the virus and its host. Conversely, with globalization, movement of plant material is increasingly more common and often a point of dispute between countries. HTS could potentially resolve these issues given its capacity to detect and discover. Although many pipelines are available for plant virus discovery, all share a common backbone. A description of the process of plant virus detection and discovery from HTS data are presented, providing a summary of the different pipelines available for scientists’ utility in their research.


F1000Research ◽  
2019 ◽  
Vol 8 ◽  
pp. 150 ◽  
Author(s):  
Dickson Aruhomukama ◽  
Ivan Sserwadda ◽  
Gerald Mboowa

Bacterial infections involving antibiotic resistant gram-negative bacteria continue to increase and represent a major global public health concern. Resistance to antibiotics in these bacteria is mediated by chromosomal and/or acquired resistance mechanisms, these give rise to multi-drug resistant (MDR) or extensive drug resistant (XDR) bacterial strains. Most recently, a novel acquired plasmid mediated resistance mechanism to colistin, an antibiotic that had been set apart as the last resort antibiotic in the treatment of infections involving MDR and XDR gram-negative bacteria, has been reported. Plasmid mediated colistin resistant gram-negative bacteria have been described to be pan-drug resistant, implying a state devoid of alternative antibiotic therapeutic options. This review describes the evolution of antibiotic resistance to plasmid mediated colistin resistance, and discusses the potential role of high-throughput sequencing technologies, genomics and bioinformatics towards improving antibiotic resistance surveillance, the search for novel drug targets and precision antibiotic therapy focused at combating colistin resistance, and antimicrobial resistance as a whole.


Biotecnia ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 5-16
Author(s):  
Estefanía Garibay-Valdez ◽  
Marcel Martínez-Porchas ◽  
Kadiya Calderón ◽  
Teresa Gollas-Galván ◽  
Luis R. Martínez- Córdova ◽  
...  

La microbiota del tracto digestivo es diversa y provee grandes beneficios al hospedero; participando en múltiples funciones relacionadas con su estado de salud, nutrición y crecimiento. Recientemente ha cobrado relevancia el estudio del papel de la microbiota en organismos de importancia acuícola, incluyendo a camarones peneidos. Los estudios pioneros en conocer la relación de los microorganismos en el desarrollo de camarones peneidos utilizaron técnicas dependientes de cultivo. A pesar de los novedosos hallazgos, esto representó solo una pequeña fracción del total de la población; sin embargo, estas primeras aproximaciones permitieron vislumbrar el rol relevante de la microbiota en la biología de estos crustáceos. Más tarde, el desarrollo de métodos basados en técnicas moleculares extendió el panorama con nuevos registros de bacterias no cultivables en estos ambientes, elucidando el efecto de diversos factores incluyendo dieta, antibióticos, probióticos, prebióticos y enfermedades sobre la modulación de la microbiota del tracto digestivo. Sin embargo, el desarrollo de técnicas de secuenciación masiva de alto rendimiento, comenzó a proporcionar bases de datos más robustas, permitiendo conocer no solo qué microorganismos están presentes en un organismo dado, sino también conocer sus funciones y roles potenciales. Hasta el momento se cuenta con descripciones de la composición de la microbiota del tracto digestivo de camarones peneidos y del como el manejo de estos microorganimos tiene beneficios en la respuesta productiva y estado de salud; sin embargo, es necesario continuar comprendiendo la relación microbiotahospedero. La presente revisión analiza la situación actual y plantea las perspectivas futuras para el estudio de la microbiota de camarones peneidos.ABSTRACTThe digestive tract microbiota is diverse and can provide great benefits to the host, participating in multiple functions related to its health, nutrition and growth. Recently, the microbiota study of important aquaculture species including penaeid shrimp has gained relevance. The first research efforts in the knowledge of the relationship between microorganisms and penaeid shrimp development used culture-dependent techniques. In spite of the novel findings, this represented only a small fraction of the total population; however, these first approaches allowed knowing the relevant role of microbiota in the biology of these crustaceans. Later, the development of methods based on molecular techniques, increased the panorama with new records of nonculturable bacteria in these environments, elucidating the effect of diverse factors including diet, antibiotics, probiotics, prebiotics, and disease on the digestive tract microbiota modulation. However, the rise of high throughput sequencing, began providing robust datasets, allowing to know not only which microbes are present in a given organism, but reveal their functions and potential roles. So far, descriptions of the microbiota composition of the digestive tract of penaeid shrimp are available, as well as on how the management of these microorganisms benefits the productive response and health status; however, it is necessary to continue comprehending the microbiota-host relationship. The present review analyzes the current situation and future perspectives in the study of penaeid shrimp microbiota


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 2392-2392 ◽  
Author(s):  
Ilango Balakrishnan ◽  
Xiaodong Yang ◽  
Beverly Torok-Storb ◽  
Jay Hesselberth ◽  
Manoj M Pillai

Abstract Abstract 2392 There is increasing recognition of the role of small noncoding RNAs in post-transcriptional regulation of gene expression in diverse tissues of eukaryotic organisms including vertebrates. MicroRNAs (miRNAs) are the best studied amongst these small RNAs and are thought to act by binding to the 3' untranslated regions (3' UTRs) of mature mRNAs in a sequence-specific fashion and preventing the initiation of peptide translation and/ or initiating mRNA degradation. Recent evidence suggests that miRNA-based regulation might involve binding to regions other than 3' UTRs including coding regions. Current approaches to defining miRNA-mRNA interactions are mostly restricted to those based on bio-informatic prediction, protein down-regulation following in-vitro transfection of miRNA precursors and luciferase assays to determine binding to 3' UTRs. None of these methods however show direct interaction between a specific miRNA and its purported target RNA. Bio-informatics-based approaches are also prone to false positive and negative results given the short length of sequence matching, and reliance on heuristics and cross-species conservation. Newer genome-wide approaches like HITS-CLIP (High Throughput Sequencing following Cross Linked Immuno Precipitation, or CLIP-Seq) overcome some of these limitations by directly isolating the miRNA-mRNA interactome bound to argonaute (AGO), a critical component of the rna-induced silencing complex (RISC)1. HITS-CLIP utilizes the ability of ultraviolet (UV) light to cross-link RNAs to proteins in their close proximity. The crosslinked miRNA-mRNA-Ago complexes are then isolated and the RNA reverse transcribed to cDNA libraries and sequenced by next generation sequencing (NGS). Given the widespread role of miRNAs in several vertebrate tissues, we hypothesized that miRNA-regulation of gene expression is operant in the hematopoietic microenvironment (ME) and thus contributes to regulation of hematopoiesis. We hence used HITS-CLIP to analyze the miRNA-mRNA interactome of three key cellular components of the ME: stromal cells, endothelium and macrophages. We have previously reported on the use of the stromal cell lines Hs27a and Hs5 to define specific functional niches within the ME. Hs27a can functionally support primitive hematopoietic stem and progenitor cells (HSPC) in cobblestone areas (CSAs) and express high levels of factors known to support HSPC such as SDF1, Jagged1 and Angiopoietin1. In contrast, Hs5 drives HSPC to mature lineages and secretes high levels of cytokines like IL1, IL6 and GCSF. Human umbilical vein endothelial cells (HUVECs) and MCSF-treated CD14+ cells were utilized for the endothelial and macrophage cultures respectively. The HITS-CLIP datasets from each of these populations were enriched for a putative binding site for miR-9 in the coding region of Matrix Metalloproteinase 2 (MMP2) mRNA. MMP2 belongs to a family of endopeptidases critical in the remodeling of extracellular matrix in several tissues and in the egress/ homing of HSPC to their functional niches in the ME. Functional binding of miR-9 to MMP2 was validated by Western-blotting of stromal cells transfected with miR-9 which revealed > 50% reduction of protein levels when compared to control-transfected cells. This was also confirmed by gelatin zymography which showed significantly reduced MMP2 activity in stromal cells transfected with miR-9. Finally, to confirm direct binding of miR-9 to the putative binding region on the MMP2 transcript, we cloned this microRNA responsive region (MRE) downstream of the Renilla luciferase gene and assayed its activity by luciferase assays. MiR-9 transfection down-regulated luciferase activity > 50% confirming direct binding to the MRE. Our results show that genome-wide approaches such as HITS-CLIP can be used to define in vivo miRNA-mRNA interactions in the ME and should be considered in studies that define such interactions given the significant false-positive and false negative results associated with approaches based on bio-informatics alone. The approach can also define specific interactions between miRNAs and mRNAs such as MMP2, of relevance to regulation of the hematopoietic ME. Disclosures: No relevant conflicts of interest to declare.


ExRNA ◽  
2019 ◽  
Vol 1 (1) ◽  
Author(s):  
Fangfang Jin ◽  
Yuling Sun

Abstract Procambarus clarkii is one of the important economic species in China and has been served as tasty food in recent years after being introduced to Nanjing. Significant problems of environment factors, such as salinity, pH and temperature, especially salinity, has the potential to result in significant economic losses in many crayfish-producing farms in China. miRNAs are a kind of ~ 22 nucleotide small non coding RNAs which were encoded by plants, animals and some viruses with functions in RNA silencing or post-transcription regulation. We constructed four sRNA library of P. clarkia from different tissues and treatments by using high-throughput sequencing technology. A total of 101 conserved miRNAs and two novel pre-miRNAs were identified and RT-qPCR were further performed to confirm existence of part of identified miRNAs. A genome wide expression profile of salt-tolerance miRNAs was proved and three miRNAs were further validated by RT-qPCR with dynamic response to different salinity stages. The study of miRNAs in P. clarkia can help us better understanding the role of miRNAs in salt-tolerance in P. clarkia.


2017 ◽  
Vol 55 (6) ◽  
pp. 1920-1927 ◽  
Author(s):  
Jim Werngren ◽  
Erik Alm ◽  
Mikael Mansjö

ABSTRACTPyrazinamide (PZA) is a key component for the effective treatment of drug-susceptible and PZA-susceptible multidrug-resistant (MDRPZA-S) tuberculosis (TB).pncAgene mutations are usually detected in a clear majority (>90%) of PZA-resistant strains but obviously not in all. Rapid and reliable PZA drug susceptibility testing (DST) is critical whenever PZA is to be used in a treatment regimen, not least for the treatment of MDRPZA-STB. In this study, we selected 26 PZA-resistant isolates reported to carry a wild-typepncAgene. To confirm resistance, susceptibility testing was repeated using 100 mg/liter and 200 mg/liter PZA for all the 26 isolates and Sanger sequencing was repeated on the 18 isolates that remained PZA resistant. Apart from the eight isolates initially misclassified as PZA resistant, the retests identified three factors responsible for the phenotype-genotype discrepancy:panDorrpsAmutations identified by whole-genome sequencing (WGS) (n= 7), heteroresistance (n= 8), and mixed populations withMycobacterium avium(n= 3). Additionally, we performed WGS on 400 PZA-susceptible isolates and 15 consecutive MDRPZA-Rclinical isolates. Of the 400 PZA-susceptible isolates, only 1 harbored a nonsynonymouspncAmutation (Thr87Met), whereas a nonsynonymousrpsAmutation was found in 17 isolates. None of these isolates carried a nonsynonymouspanDmutation, while all 15 of the MDRPZA-Risolates harbored a nonsynonymouspncAmutation. Our findings indicate that it is necessary to consider the occurrence ofpanDmutations in PZA-resistant isolates, as well as heteroresistance, for the development and evaluation of new molecular techniques to ensure high-quality DST performance. The identification of nonsynonymousrpsAmutations in both PZA-susceptible and PZA-resistant isolates also implies that further studies are needed in order to determine the role ofrpsAin PZA resistance.


Plant Disease ◽  
2020 ◽  
Author(s):  
Zachary David Zalewski ◽  
Rae Page ◽  
Richard Lankau ◽  
Patricia McManus

Cranberry fruit rot (CFR) is an economically important disease caused by at least 10 species of filamentous fungi. Despite the application of fungicides, incidence of CFR is sometimes high, raising the possibility of a role for microbes other than fungi in the CFR complex. Isolation of microbes from rotten berries on media that favor either bacteria or yeasts resulted in mucoid colonies from fewer than 15% of dry-harvested rotten berries but up to 60% of wet-harvested berries. The mucoid colonies were identified as yeasts, primarily in the family Saccharomycetaceae. Inoculation of sound berries with three yeasts, Hanseniaspora uvarum, Pichia fermentans, and Pichia terricola, resulted in significantly higher incidence and severity of rot symptoms compared to mock-inoculated controls; these yeasts were recovered from inoculated berries, providing evidence of their pathogenicity. The minimum concentrations of azoxystrobin, chlorothalonil, and prothioconazole that resulted in 80% inhibition of growth compared to untreated controls (MIC80) were determined for a subset of yeasts. In general, MIC80s were higher for azoxystrobin and prothioconazole (usually >64 µg/ml) than for chlorothalonil (usually ≤1 µg/ml). To complement culture-dependent studies, DNA was isolated from wet- and dry-harvested rotten berries, and fungi were identified to the level of family by high-throughput sequencing of the fungal internal transcribed spacer region (ITS2). There were no fungal families consistently detected among samples by one method (culturing or high-throughput sequencing) and missed by the other that have not previously been reported in cranberry; however, some fungal families were found to be more abundant by one method versus the other. Harvest method (wet or dry) had a significant effect on the composition of fungal communities of rotten berries (P < 0.001), and operational taxonomic units representing the Saccharomycetaceae were more abundant in wet- than dry-harvested berries. Taken together, the results suggest that some yeasts are pathogenic to cranberry and may be especially relevant in wet-harvested berries.


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