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1.
bioRxiv ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38187527

RESUMO

Advancements in microscopy techniques and computing technologies have enabled researchers to digitally reconstruct brains at micron scale. As a result, community efforts like the BRAIN Initiative Cell Census Network (BICCN) have generated thousands of whole-brain imaging datasets to trace neuronal circuitry and comprehensively map cell types. This data holds valuable information that extends beyond initial analyses, opening avenues for variation studies and robust classification of cell types in specific brain regions. However, the size and heterogeneity of these imaging data have historically made storage, sharing, and analysis difficult for individual investigators and impractical on a broad community scale. Here, we introduce the Brain Image Library (BIL), a public resource serving the neuroscience community that provides a persistent centralized repository for brain microscopy data. BIL currently holds thousands of brain datasets and provides an integrated analysis ecosystem, allowing for exploration, visualization, and data access without the need to download, thus encouraging scientific discovery and data reuse.

2.
BMC Biotechnol ; 23(1): 51, 2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049781

RESUMO

BACKGROUND: Goat rumen microbial communities are perceived as one of the most potential biochemical reservoirs of multi-functional enzymes, which are applicable to enhance wide array of bioprocesses such as the hydrolysis of cellulose and hemi-cellulose into fermentable sugar for biofuel and other value-added biochemical production. Even though, the limited understanding of rumen microbial genetic diversity and the absence of effective screening culture methods have impeded the full utilization of these potential enzymes. In this study, we applied culture independent metagenomics sequencing approach to isolate, and identify microbial communities in goat rumen, meanwhile, clone and functionally characterize novel cellulase and xylanase genes in goat rumen bacterial communities. RESULTS: Bacterial DNA samples were extracted from goat rumen fluid. Three genomic libraries were sequenced using Illumina HiSeq 2000 for paired-end 100-bp (PE100) and Illumina HiSeq 2500 for paired-end 125-bp (PE125). A total of 435gb raw reads were generated. Taxonomic analysis using Graphlan revealed that Fibrobacter, Prevotella, and Ruminococcus are the most abundant genera of bacteria in goat rumen. SPAdes assembly and prodigal annotation were performed. The contigs were also annotated using the DOE-JGI pipeline. In total, 117,502 CAZymes, comprising endoglucanases, exoglucanases, beta-glucosidases, xylosidases, and xylanases, were detected in all three samples. Two genes with predicted cellulolytic/xylanolytic activities were cloned and expressed in E. coli BL21(DE3). The endoglucanases and xylanase enzymatic activities of the recombinant proteins were confirmed using substrate plate assay and dinitrosalicylic acid (DNS) analysis. The 3D structures of endoglucanase A and endo-1,4-beta xylanase was predicted using the Swiss Model. Based on the 3D structure analysis, the two enzymes isolated from goat's rumen metagenome are unique with only 56-59% similarities to those homologous proteins in protein data bank (PDB) meanwhile, the structures of the enzymes also displayed greater stability, and higher catalytic activity. CONCLUSIONS: In summary, this study provided the database resources of bacterial metagenomes from goat's rumen fluid, including gene sequences with annotated functions and methods for gene isolation and over-expression of cellulolytic enzymes; and a wealth of genes in the metabolic pathways affecting food and nutrition of ruminant animals.


Assuntos
Celulase , Celulases , Animais , Celulase/metabolismo , Metagenoma , Cabras/genética , Cabras/metabolismo , Cabras/microbiologia , Rúmen/metabolismo , Rúmen/microbiologia , Escherichia coli/genética , Bactérias , Celulases/genética , Celulose
4.
Nat Cancer ; 4(1): 128-147, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36585450

RESUMO

The AURORA US Metastasis Project was established with the goal to identify molecular features associated with metastasis. We assayed 55 females with metastatic breast cancer (51 primary cancers and 102 metastases) by RNA sequencing, tumor/germline DNA exome and low-pass whole-genome sequencing and global DNA methylation microarrays. Expression subtype changes were observed in ~30% of samples and were coincident with DNA clonality shifts, especially involving HER2. Downregulation of estrogen receptor (ER)-mediated cell-cell adhesion genes through DNA methylation mechanisms was observed in metastases. Microenvironment differences varied according to tumor subtype; the ER+/luminal subtype had lower fibroblast and endothelial content, while triple-negative breast cancer/basal metastases showed a decrease in B and T cells. In 17% of metastases, DNA hypermethylation and/or focal deletions were identified near HLA-A and were associated with reduced expression and lower immune cell infiltrates, especially in brain and liver metastases. These findings could have implications for treating individuals with metastatic breast cancer with immune- and HER2-targeting therapies.


Assuntos
Neoplasias Mamárias Animais , Neoplasias de Mama Triplo Negativas , Feminino , Animais , Humanos , Multiômica , Mama , Neoplasias de Mama Triplo Negativas/genética , Metilação de DNA/genética , Neoplasias Mamárias Animais/genética , Epigênese Genética/genética , Microambiente Tumoral/genética
5.
Sci Data ; 9(1): 449, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896564

RESUMO

Recent advances in fluorescence microscopy techniques and tissue clearing, labeling, and staining provide unprecedented opportunities to investigate brain structure and function. These experiments' images make it possible to catalog brain cell types and define their location, morphology, and connectivity in a native context, leading to a better understanding of normal development and disease etiology. Consistent annotation of metadata is needed to provide the context necessary to understand, reuse, and integrate these data. This report describes an effort to establish metadata standards for three-dimensional (3D) microscopy datasets for use by the Brain Research through Advancing Innovative Neurotechnologies® (BRAIN) Initiative and the neuroscience research community. These standards were built on existing efforts and developed with input from the brain microscopy community to promote adoption. The resulting 3D Microscopy Metadata Standards (3D-MMS) includes 91 fields organized into seven categories: Contributors, Funders, Publication, Instrument, Dataset, Specimen, and Image. Adoption of these metadata standards will ensure that investigators receive credit for their work, promote data reuse, facilitate downstream analysis of shared data, and encourage collaboration.


Assuntos
Metadados , Microscopia , Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Conjuntos de Dados como Assunto , Humanos , Microscopia/métodos , Microscopia/normas
6.
Artigo em Inglês | MEDLINE | ID: mdl-30279399

RESUMO

Lucina pectinata is a clam that lives in sulfide-rich environments and houses intracellular sulfide-oxidizing endosymbionts. To identify new Lucina pectinata proteins, we produced libraries for genome and transcriptome sequencing and assembled them de novo. We searched for histone-like sequences using the Lucina pectinata histone H3 partial nucleotide sequence against our previously described genome assembly to obtain the complete coding region and identify H3 coding sequences from mollusk sequences in Genbank. Solen marginatus histone nucleotide sequences were used as query sequences using the genome and transcriptome assemblies to identify the Lucina pectinata H1, H2A, H2B and H4 genes and mRNAs and obtained the complete coding regions of the five histone genes by RT-PCR combined with automated Sanger DNA sequencing. The amino acid sequence conservation between the Lucina pectinata and Solen marginatus histones was: 77%, 93%, 83%, 96% and 97% for H1, H2A, H2B, H3 and H4, respectively. As expected, the H3 and H4 proteins were the most conserved and the H1 proteins were most similar to H1's from aquatic organisms like Crassostrea gigas, Aplysia californica, Mytilus trossulus and Biomphalaria glabrata. The Lucina pectinata draft genome and transcriptome assemblies, obtained by semiconductor sequencing, were adequate for identification of conserved proteins as evidenced by our results for the histone genes.


Assuntos
Bivalves/genética , Evolução Molecular , Histonas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sequência Conservada , Éxons , Ambientes Extremos , Filogenia , Porto Rico , RNA Mensageiro/genética , Análise de Sequência de DNA , Áreas Alagadas
7.
PLoS One ; 13(9): e0203218, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30180199

RESUMO

Luciferases, aryl- and fatty-acyl CoA synthetases, and non-ribosomal peptide synthetase proteins belong to the class I adenylate-forming enzyme superfamily. The reaction catalyzed by the adenylate-forming enzymes is categorized by a two-step process of adenylation and thioesterification. Although all of these proteins perform a similar two-step process, each family may perform the process to yield completely different results. For example, luciferase proteins perform adenylation and oxidation to produce the green fluorescent light found in fireflies, while fatty-acyl CoA synthetases perform adenylation and thioesterification with coenzyme A to assist in metabolic processes involving fatty acids. This study aligned a total of 374 sequences belonging to the adenylate-forming superfamily. Analysis of the sequences revealed five fully conserved residues throughout all sequences, as well as 78 more residues conserved in at least 60% of sequences aligned. Conserved positions are involved in magnesium and AMP binding and maintaining enzyme structure. Also, ten conserved sequence motifs that included most of the conserved residues were identified. A phylogenetic tree was used to assign sequences into nine different groups. Finally, group entropy analysis identified novel conservations unique to each enzyme group. Common group-specific positions identified in multiple groups include positions critical to coordinating AMP and the CoA-bound product, a position that governs active site shape, and positions that help to maintain enzyme structure through hydrogen bonds and hydrophobic interactions. These positions could serve as excellent targets for future research.


Assuntos
Coenzima A Ligases/classificação , Coenzima A Ligases/genética , Luciferases/classificação , Luciferases/genética , Peptídeo Sintases/classificação , Peptídeo Sintases/genética , Monofosfato de Adenosina/biossíntese , Animais , Coenzima A Ligases/metabolismo , Simulação por Computador , Sequência Conservada , Humanos , Luciferases/metabolismo , Modelos Moleculares , Peptídeo Sintases/metabolismo , Filogenia , Homologia de Sequência de Aminoácidos
8.
FEBS Open Bio ; 7(10): 1480-1498, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28979838

RESUMO

Heme oxygenases (HO) catalyze the breakdown of heme, aiding the recycling of its components. Several other enzymes have homologous tertiary structures to HOs, while sharing little sequence homology. These homologues include thiaminases, the hydroxylase component of methane monooxygenases, and the R2 component of Class I ribonucleotide reductases (RNR). This study compared these structural homologues of HO, using a large number of protein sequences for each homologue. Alignment of a total of 472 sequences showed little sequence conservation, with no residues having conservation in more than 80% of aligned sequences and only five residues conserved in at least 60% of the sequences. Fourteen additional positions, most of which were critical for hydrophobic packing, displayed amino acid similarity of 60% or higher. Ten conserved sequence motifs were identified in HOs and RNRs. Phylogenetic analysis verified the existence of the four distinct groups of HO homologues, which were then analyzed by group entropy analysis to identify residues critical to the unique function of each enzyme. Other methods for determining functional residues were also performed. Several common index positions identified represent critical evolutionary changes that resulted in the unique function of each enzyme, suggesting potential targets for site-directed mutagenesis. These positions included residues that coordinate ligands, form the active sites, and maintain enzyme structure. ENZYMES: Heme oxygenase (EC 1.14.14.18), methane monooxygenase (EC 1.14.13.25), ribonucleotide reductase (EC 1.17.4.1), thiaminase II (EC 3.5.99.2).

9.
Genome Announc ; 4(4)2016 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-27540056

RESUMO

We report here the draft genome sequence of Acinetobacter baumannii strain M3AC14-8, sequence type 2 (ST2), carrying a chromosomally carried blaKPC-2 gene. The draft genome consists of a total length of 4.11 Mbp and a G+C content of 39.25%.

10.
Microarrays (Basel) ; 4(2): 287-310, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26388997

RESUMO

Establishing how a series of potentially important genes might relate to each other is relevant to understand the origin and evolution of illnesses, such as cancer. High-throughput biological experiments have played a critical role in providing information in this regard. A special challenge, however, is that of trying to conciliate information from separate microarray experiments to build a potential genetic signaling path. This work proposes a two-step analysis pipeline, based on optimization, to approach meta-analysis aiming to build a proxy for a genetic signaling path.

11.
BMC Genomics ; 16: 358, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25948401

RESUMO

BACKGROUND: Guinea fowl (Numidia meleagris) production as an alternative source of meat and poultry has shown potential for economic viability. However, there has been little progress in characterizing the transcriptome of the guinea fowl. In this study RNA-sequencing and de novo transcriptome assembly of several Guinea fowl tissues (pancreas, hypothalamus, liver, bone marrow and bursa) which play key roles in regulating feed intake, satiety, and immune function was performed using Illumina's Hi-Seq 2000. RESULTS: 74 million sequences were generated and assembled into 96,492 contigs using the Trinity software suite. Over 39,000 of these transcripts were found to have in silico translated protein sequences that are homologous to chicken protein sequences. Gene ontology analysis uncovered 416 transcripts with metabolic functions and 703 with immune function. CONCLUSION: The transcriptome information presented here will support the development of molecular approaches to improve production efficiency of the guinea fowl and other avian species.


Assuntos
Galliformes/imunologia , Galliformes/metabolismo , Perfilação da Expressão Gênica , Animais , Bases de Dados Genéticas , Galliformes/genética , Anotação de Sequência Molecular , Especificidade de Órgãos , Análise de Sequência de RNA , Homologia de Sequência do Ácido Nucleico , Software
12.
Genome Announc ; 3(2)2015 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-25858845

RESUMO

We report the draft genome of a multidrug resistant, Klebsiella pneumoniae carbapenemase (KPC)-producing Acinetobacter baumannii strain M3AC9-7 that belongs to the novel sequence type, ST250. The draft genome consists of a total length of 4.09 Mbp and a G+C content of 38.95%.

13.
Genome Announc ; 2(6)2014 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-25523768

RESUMO

This paper reports the draft genome sequence of new Bacillus cereus strain tsu1, isolated on an agar-cellulose plate. The draft genome sequence is 5.81 Mb, revealing 5,673 coding sequences. It contains genes for cellulose-degradation and biosynthesis pathways of polyhydroxybutyrate (PHB) and 8 rRNA genes (5S, 16S, and 23S).

14.
Mol Inform ; 30(10): 896-906, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27468109

RESUMO

Plant sesquiterpene synthases, a subset of the terpene synthase superfamily, are a mechanistically diverse family of enzymes capable of synthesizing hundreds of complex compounds with high regio- and stereospecificity and are of biological importance due to their role in plant defense mechanisms. In the current report we describe a large-scale, high-resolution phylogenetic analysis of ∼200 plant sesquiterpene synthases integrated with structural and experimental data that address these issues. We observe that all sequences that cluster together on the phylogenetic tree into well-defined groups share at least the first reaction in the catalytic mechanism subsequent to the initial ionization step and many share steps beyond this down to proton transfers between the enzyme and substrate. Most significant is the previously unreported high conservation of an Asp-Tyr-Asp triad. Due to its high conservation, patterns in the phylogenetic tree as well as experimental and modeling results, we suggest that this Asp-Tyr-Asp triad is an important functional element responsible for many proton transfers to and from the substrate and intermediates along the plant sesquiterpene synthase catalytic cycle and whose position can be tuned by residues outside the active site that can lead to the evolution of novel enzyme function.

15.
PLoS One ; 5(11): e13999, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21085574

RESUMO

BACKGROUND: Phylogenetic study of protein sequences provides unique and valuable insights into the molecular and genetic basis of important medical and epidemiological problems as well as insights about the origins and development of physiological features in present day organisms. Consensus phylogenies based on the bootstrap and other resampling methods play a crucial part in analyzing the robustness of the trees produced for these analyses. METHODOLOGY: Our focus was to increase the number of bootstrap replications that can be performed on large protein datasets using the maximum parsimony, distance matrix, and maximum likelihood methods. We have modified the PHYLIP package using MPI to enable large-scale phylogenetic study of protein sequences, using a statistically robust number of bootstrapped datasets, to be performed in a moderate amount of time. This paper discusses the methodology used to parallelize the PHYLIP programs and reports the performance of the parallel PHYLIP programs that are relevant to the study of protein evolution on several protein datasets. CONCLUSIONS: Calculations that currently take a few days on a state of the art desktop workstation are reduced to calculations that can be performed over lunchtime on a modern parallel computer. Of the three protein methods tested, the maximum likelihood method scales the best, followed by the distance method, and then the maximum parsimony method. However, the maximum likelihood method requires significant memory resources, which limits its application to more moderately sized protein datasets.


Assuntos
Biologia Computacional/métodos , Filogenia , Proteínas/genética , Algoritmos , Animais , Humanos , Proteínas/classificação , Reprodutibilidade dos Testes , Alinhamento de Sequência/métodos , Software
16.
Curr Protoc Bioinformatics ; Chapter 3: Unit3.10, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18428720

RESUMO

In this unit a protocol is described for predicting the structure of simple transmembrane a-helical bundles. The protocol is based on a global molecular dynamics search (GMDS) of the configuration space of the helical bundle, yielding several candidate structures. The correct structure among these candidates is selected using information from silent amino acid substitutions, employing the premise that only the correct structure must (by definition) accept all of the silent amino acid substitutions. Thus, the correct structure is found by repeating the GMDS for several close homologs and selecting the structure that persists in all of the trials.


Assuntos
Algoritmos , Sistemas de Gerenciamento de Base de Dados , Bases de Dados Genéticas , Armazenamento e Recuperação da Informação/métodos , Análise de Sequência de DNA/métodos , Análise de Sequência de Proteína/métodos , Alinhamento de Sequência/métodos , Software
17.
Biotechniques ; 32(3): 572-4, 576, 578 passim, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11911661

RESUMO

We present an overview of multiple sequence alignments to outline the practical consequences for the choices among different techniques and parameters. We begin with a discussion of the scoring methods for quantifying the quality of a multiple sequence alignment, followed by a discussion of the algorithms implemented within a variety of multiple sequence alignment programs. We also discuss additional alignment details such as gap penalty and distance metrics. The paper concludes with a discussion on how to improve alignment quality and the limitations of the techniques described in this paper


Assuntos
Evolução Molecular , Modelos Genéticos , Alinhamento de Sequência/métodos , Algoritmos , Software
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