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1.
Pharmacoepidemiol Drug Saf ; 33(6): e5801, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38798093

RESUMO

PURPOSE: Antiretrovirals (ARVs) are life-saving drugs used for the treatment and prevention of HIV infection and antiviral drugs (AVs) for the treatment of chronic HBV infection. ARVs have proven highly effective in reducing perinatal HIV transmission, however the risk of birth defects from prenatal exposure to ARVs/AVs is an ongoing concern. The Antiretroviral Pregnancy Registry (APR), an international, prospective exposure-registration cohort study, monitors ARV and AV use in pregnancy for early signals of teratogenicity. This communication reports results of 30-years' experience of ARV/AV exposure during pregnancy and lessons learned through continuous quality improvement. METHODS AND RESULTS: Birth defect prevalence is estimated and compared to internal and external groups. Statistical inference is based on exact methods for binomial proportions. Between 2006 and 2023, cumulative enrollment more than tripled from 6893 to 25 960 pregnancies and ARVs/AVs monitored increased from 29 to 222. Through January 2023, there were 21 636 live births and 631 outcomes with birth defects, for overall prevalence of 2.9/100 live births (95% CI 2.7, 3.2). The birth defect prevalence was 3.0% (95% CI 2.7%, 3.3%) among first trimester exposures and 2.8% (95% CI 2.5%, 3.2%) among second/third trimester exposures (prevalence ratio 1.04 [95% CI 0.89, 1.21]). CONCLUSIONS: Birth defect prevalence is not statistically significantly different between first trimester ARV/AV pregnancy exposures compared to second/third trimester exposures and is also not different from two population-based surveillance systems: 2.72/100 live births reported in the Metropolitan Atlanta Congenital Defects Program (MACDP); and 4.17/100 live births from the Texas Birth Defects Registry (TBDR).


Assuntos
Anormalidades Induzidas por Medicamentos , Infecções por HIV , Complicações Infecciosas na Gravidez , Sistema de Registros , Humanos , Gravidez , Feminino , Estudos Prospectivos , Anormalidades Induzidas por Medicamentos/epidemiologia , Anormalidades Induzidas por Medicamentos/etiologia , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Adulto , Prevalência , Recém-Nascido , Antirretrovirais/uso terapêutico , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/uso terapêutico , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Adulto Jovem , Anormalidades Congênitas/epidemiologia , Estudos de Coortes
2.
bioRxiv ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38260250

RESUMO

Fatty acid ß-oxidation (FAO) is a central catabolic pathway with broad implications for organismal health. However, various fatty acids are largely incompatible with standard FAO machinery until they are modified by other enzymes. Included among these are the 4-hydroxy acids (4-HAs)-fatty acids hydroxylated at the 4 (γ) position-which can be provided from dietary intake, lipid peroxidation, and certain drugs of abuse. Here, we reveal that two atypical and poorly characterized acyl-CoA dehydrogenases (ACADs), ACAD10 and ACAD11, drive 4-HA catabolism in mice. Unlike other ACADs, ACAD10 and ACAD11 feature kinase domains N-terminal to their ACAD domains that phosphorylate the 4-OH position as a requisite step in the conversion of 4-hydroxyacyl-CoAs into 2-enoyl-CoAs-conventional FAO intermediates. Our ACAD11 cryo-EM structure and molecular modeling reveal a unique binding pocket capable of accommodating this phosphorylated intermediate. We further show that ACAD10 is mitochondrial and necessary for catabolizing shorter-chain 4-HAs, whereas ACAD11 is peroxisomal and enables longer-chain 4-HA catabolism. Mice lacking ACAD11 accumulate 4-HAs in their plasma while comparable 3- and 5-hydroxy acids remain unchanged. Collectively, this work defines ACAD10 and ACAD11 as the primary gatekeepers of mammalian 4-HA catabolism and sets the stage for broader investigations into the ramifications of aberrant 4-HA metabolism in human health and disease.

3.
Biomolecules ; 13(2)2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36830626

RESUMO

Insulin is amongst the human genome's most well-studied genes/proteins due to its connection to metabolic health. Within this article, we review literature and data to build a knowledge base of Insulin (INS) genetics that influence transcription, transcript processing, translation, hormone maturation, secretion, receptor binding, and metabolism while highlighting the future needs of insulin research. The INS gene region has 2076 unique variants from population genetics. Several variants are found near the transcriptional start site, enhancers, and following the INS transcripts that might influence the readthrough fusion transcript INS-IGF2. This INS-IGF2 transcript splice site was confirmed within hundreds of pancreatic RNAseq samples, lacks drift based on human genome sequencing, and has possible elevated expression due to viral regulation within the liver. Moreover, a rare, poorly characterized African population-enriched variant of INS-IGF2 results in a loss of the stop codon. INS transcript UTR variants rs689 and rs3842753, associated with type 1 diabetes, are found in many pancreatic RNAseq datasets with an elevation of the 3'UTR alternatively spliced INS transcript. Finally, by combining literature, evolutionary profiling, and structural biology, we map rare missense variants that influence preproinsulin translation, proinsulin processing, dimer/hexamer secretory storage, receptor activation, and C-peptide detection for quasi-insulin blood measurements.


Assuntos
Diabetes Mellitus Tipo 1 , Medicina de Precisão , Humanos , Proinsulina , Diabetes Mellitus Tipo 1/genética , Pâncreas , Genômica
4.
J Am Heart Assoc ; 12(5): e027556, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36802928

RESUMO

Background The lifetime journey of patients with single-ventricle congenital heart disease is characterized by long-term challenges that are incompletely understood and still unfolding. Health care redesign requires a thorough understanding of this journey to create and implement solutions that improve outcomes. This study maps the lifetime journey of individuals with single-ventricle congenital heart disease and their families, identifies the most meaningful outcomes to them, and defines significant challenges in the journey. Methods and Results This qualitative research study involved experience group sessions and 1:1 interviews of patients, parents, siblings, partners, and stakeholders. Journey maps were created. The most meaningful outcomes to patients and parents and significant gaps in care were identified across the life journey. A total of 142 participants from 79 families and 28 stakeholders were included. Lifelong and life-stage specific journey maps were created. The most meaningful outcomes to patients and parents were identified and categorized using a "capability (doing the things in life you want to), comfort (experience of physical/emotional pain/distress), and calm (experiencing health care with the least impact on daily life)" framework. Gaps in care were identified and classified into areas of ineffective communication, lack of seamless transitions, lack of comprehensive support, structural deficiencies, and insufficient education. Conclusions There are significant gaps in care during the lifelong journey of individuals with single-ventricle congenital heart disease and their families. A thorough understanding of this journey is a critical first step in developing initiatives to redesign care around their needs and priorities. This approach can be used for people with other forms of congenital heart disease and other chronic conditions. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04613934.


Assuntos
Cardiopatias Congênitas , Coração Univentricular , Humanos , Pais/psicologia , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/terapia , Dor , Comunicação
5.
Genes (Basel) ; 14(1)2023 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-36672963

RESUMO

The SOX transcription factor family is pivotal in controlling aspects of development. To identify genotype-phenotype relationships of SOX proteins, we performed a non-biased study of SOX using 1890 open-reading frame and 6667 amino acid sequences in combination with structural dynamics to interpret 3999 gnomAD, 485 ClinVar, 1174 Geno2MP, and 4313 COSMIC human variants. We identified, within the HMG (High Mobility Group)- box, twenty-seven amino acids with changes in multiple SOX proteins annotated to clinical pathologies. These sites were screened through Geno2MP medical phenotypes, revealing novel SOX15 R104G associated with musculature abnormality and SOX8 R159G with intellectual disability. Within gnomAD, SOX18 E137K (rs201931544), found within the HMG box of ~0.8% of Latinx individuals, is associated with seizures and neurological complications, potentially through blood-brain barrier alterations. A total of 56 highly conserved variants were found at sites outside the HMG-box, including several within the SOX2 HMG-box-flanking region with neurological associations, several in the SOX9 dimerization region associated with Campomelic Dysplasia, SOX14 K88R (rs199932938) flanking the HMG box associated with cardiovascular complications within European populations, and SOX7 A379V (rs143587868) within an SOXF conserved far C-terminal domain heterozygous in 0.716% of African individuals with associated eye phenotypes. This SOX data compilation builds a robust genotype-to-phenotype association for a gene family through more robust ortholog data integration.


Assuntos
Proteínas de Grupo de Alta Mobilidade , Fatores de Transcrição SOX , Humanos , Proteínas de Grupo de Alta Mobilidade/química , Proteínas de Grupo de Alta Mobilidade/genética , Proteínas de Grupo de Alta Mobilidade/metabolismo , Fatores de Transcrição SOX/genética , Sequência de Aminoácidos , Dimerização , Genótipo , Fatores de Transcrição SOXF/genética , Fatores de Transcrição SOXF/metabolismo , Fatores de Transcrição SOXB2/genética , Fatores de Transcrição SOXB2/metabolismo , Fatores de Transcrição SOXE/genética
6.
Nutrients ; 14(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36364934

RESUMO

ß-Hydroxy-ß-methylbutyrate (HMB), a leucine metabolite, can increase skeletal muscle size and function. However, HMB may be less effective at improving muscle function in people with insufficient Vitamin D3 (25-OH-D < 30 ng/mL) which is common in middle-aged and older adults. Therefore, we tested the hypothesis that combining HMB plus Vitamin D3 (HMB + D) supplementation would improve skeletal muscle size, composition, and function in middle-aged women. In a double-blinded fashion, women (53 ± 1 yrs, 26 ± 1 kg/m2, n = 43) were randomized to take placebo or HMB + D (3 g Calcium HMB + 2000 IU D per day) during 12 weeks of sedentary behavior (SED) or resistance exercise training (RET). On average, participants entered the study Vitamin D3 insufficient while HMB + D increased 25-OH-D to sufficient levels after 8 and 12 weeks. In SED, HMB + D prevented the loss of arm lean mass observed with placebo. HMB + D increased muscle volume and decreased intermuscular adipose tissue (IMAT) volume in the thigh compared to placebo but did not change muscle function. In RET, 12-weeks of HMB + D decreased IMAT compared to placebo but did not influence the increase in skeletal muscle volume or function. In summary, HMB + D decreased IMAT independent of exercise status and may prevent the loss or increase muscle size in a small cohort of sedentary middle-aged women. These results lend support to conduct a longer duration study with greater sample size to determine the validity of the observed positive effects of HMB + D on IMAT and skeletal muscle in a small cohort of middle-aged women.


Assuntos
Colecalciferol , Força Muscular , Humanos , Pessoa de Meia-Idade , Feminino , Idoso , Colecalciferol/farmacologia , Suplementos Nutricionais , Músculo Esquelético , Método Duplo-Cego
7.
Arch Sex Behav ; 51(7): 3637-3646, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35467172

RESUMO

This study presents findings from a community survey on pup play. Pup play is a kink activity and a form of role play that is growing in popularity internationally, and gaining increasing attention in sexology, yet prior research on pup play has almost entirely employed qualitative methods and primarily involved gay and bisexual men. Using survey data of 733 pup play participants primarily from the US, but also internationally, this study reports on the demographics of participants, how they engage in pup play, its social and sexual elements, and how it relates to social identity and mental health. Unique pup names and identifying with breeds of dogs were used to foster a sense of individuality within pup play, while the majority of participants owned and wore gear when engaging in pup play. We also found significant associations between being younger and identifying as a pup. Most participants reported that pup play improved their mental health. Binary logistic regression analyses indicated that having a mental health diagnosis was associated with identifying with a more social style of pup play and self-reporting the mental health benefits of pup play. We find that the conceptualization of pup play in the existing literature to be accurate to this international sample and highlight areas where further research is needed, alongside limitations of the study.


Assuntos
Bissexualidade , Minorias Sexuais e de Gênero , Bissexualidade/psicologia , Humanos , Saúde Mental , Comportamento Sexual/psicologia , Inquéritos e Questionários
8.
Metab Eng ; 67: 112-124, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34175462

RESUMO

Polyketide synthases (PKS) and nonribosomal peptide synthetases (NRPS) comprise biosynthetic pathways that provide access to diverse, often bioactive natural products. Metabolic engineering can improve production metrics to support characterization and drug-development studies, but often native hosts are difficult to genetically manipulate and/or culture. For this reason, heterologous expression is a common strategy for natural product discovery and characterization. Many bacteria have been developed to express heterologous biosynthetic gene clusters (BGCs) for producing polyketides and nonribosomal peptides. In this article, we describe tools for using Pseudomonas putida, a Gram-negative soil bacterium, as a heterologous host for producing natural products. Pseudomonads are known to produce many natural products, but P. putida production titers have been inconsistent in the literature and often low compared to other hosts. In recent years, synthetic biology tools for engineering P. putida have greatly improved, but their application towards production of natural products is limited. To demonstrate the potential of P. putida as a heterologous host, we introduced BGCs encoding the synthesis of prodigiosin and glidobactin A, two bioactive natural products synthesized from a combination of PKS and NRPS enzymology. Engineered strains exhibited robust production of both compounds after a single chromosomal integration of the corresponding BGC. Next, we took advantage of a set of genome-editing tools to increase titers by modifying transcription and translation of the BGCs and increasing the availability of auxiliary proteins required for PKS and NRPS activity. Lastly, we discovered genetic modifications to P. putida that affect natural product synthesis, including a strategy for removing a carbon sink that improves product titers. These efforts resulted in production strains capable of producing 1.1 g/L prodigiosin and 470 mg/L glidobactin A.


Assuntos
Peptídeos Cíclicos/biossíntese , Prodigiosina/biossíntese , Pseudomonas putida , Vias Biossintéticas , Engenharia Metabólica , Microrganismos Geneticamente Modificados , Família Multigênica , Pseudomonas putida/genética
9.
ACS Chem Biol ; 16(1): 125-135, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33373180

RESUMO

Siderophores are iron-chelating molecules produced by microorganisms and plants to acquire exogenous iron. Siderophore biosynthetic enzymology often produces elaborate and unique molecules through unusual reactions to enable specific recognition by the producing organisms. Herein, we report the structure of two siderophore analogs from Agrobacterium fabrum strain C58, which we named fabrubactin (FBN) A and FBN B. Additionally, we characterized the substrate specificities of the NRPS and PKS components. The structures suggest unique Favorskii-like rearrangements of the molecular backbone that we propose are catalyzed by the flavin-dependent monooxygenase, FbnE. FBN A and B contain a 1,1-dimethyl-3-amino-1,2,3,4-tetrahydro-7,8-dihydroxy-quinolin (Dmaq) moiety previously seen only in the anachelin cyanobacterial siderophores. We provide evidence that Dmaq is derived from l-DOPA and propose a mechanism for the formation of the mature Dmaq moiety. Our bioinformatic analyses suggest that FBN A and B and the anachelins belong to a large and diverse siderophore family widespread throughout the Rhizobium/Agrobacterium group, α-proteobacteria, and cyanobacteria.


Assuntos
Agrobacterium/química , Sideróforos/biossíntese , Sideróforos/química , Monofosfato de Adenosina/metabolismo , Estrutura Molecular , Sideróforos/metabolismo , Análise Espectral/métodos , Especificidade por Substrato
10.
bioRxiv ; 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32511397

RESUMO

The SARS-CoV-2 pandemic, starting in 2019, has challenged the speed at which labs perform science, ranging from discoveries of the viral composition to handling health outcomes in humans. The small ~30kb single-stranded RNA genome of Coronaviruses makes them adept at cross species spread and drift, increasing their probability to cause pandemics. However, this small genome also allows for a robust understanding of all proteins coded by the virus. We employed protein modeling, molecular dynamic simulations, evolutionary mapping, and 3D printing to gain a full proteome and dynamicome understanding of SARS-CoV-2. The Viral Integrated Structural Evolution Dynamic Database (VIStEDD) has been established (prokoplab.com/vistedd), opening future discoveries and educational usage. In this paper, we highlight VIStEDD usage for nsp6, Nucleocapsid (N), and Spike (S) surface glycoprotein. For both nsp6 and N we reveal highly conserved surface amino acids that likely drive protein-protein interactions. In characterizing viral S protein, we have developed a quantitative dynamics cross correlation matrix insight into interaction with the ACE2/SLC6A19 dimer complex. From this quantitative matrix, we elucidated 47 potential functional missense variants from population genomic databases within ACE2/SLC6A19/TMPRSS2, warranting genomic enrichment analyses in SARS-CoV-2 patients. Moreover, these variants have ultralow frequency, but can exist as hemizygous in males for ACE2, which falls on the X-chromosome. Two noncoding variants (rs4646118 and rs143185769) found in ~9% of African descent individuals for ACE2 may regulate expression and be related to increased susceptibility of African Americans to SARS-CoV-2. This powerful database of SARS-CoV-2 can aid in research progress in the ongoing pandemic.

11.
J Biol Chem ; 295(33): 11742-11753, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32587094

RESUMO

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has challenged the speed at which laboratories can discover the viral composition and study health outcomes. The small ∼30-kb ssRNA genome of coronaviruses makes them adept at cross-species spread while enabling a robust understanding of all of the proteins the viral genome encodes. We have employed protein modeling, molecular dynamics simulations, evolutionary mapping, and 3D printing to gain a full proteome- and dynamicome-level understanding of SARS-CoV-2. We established the Viral Integrated Structural Evolution Dynamic Database (VIStEDD at RRID:SCR_018793) to facilitate future discoveries and educational use. Here, we highlight the use of VIStEDD for nsp6, nucleocapsid (N), and spike (S) surface glycoprotein. For both nsp6 and N, we found highly conserved surface amino acids that likely drive protein-protein interactions. In characterizing viral S protein, we developed a quantitative dynamics cross-correlation matrix to gain insights into its interactions with the angiotensin I-converting enzyme 2 (ACE2)-solute carrier family 6 member 19 (SLC6A19) dimer. Using this quantitative matrix, we elucidated 47 potential functional missense variants from genomic databases within ACE2/SLC6A19/transmembrane serine protease 2 (TMPRSS2), warranting genomic enrichment analyses in SARS-CoV-2 patients. These variants had ultralow frequency but existed in males hemizygous for ACE2. Two ACE2 noncoding variants (rs4646118 and rs143185769) present in ∼9% of individuals of African descent may regulate ACE2 expression and may be associated with increased susceptibility of African Americans to SARS-CoV-2. We propose that this SARS-CoV-2 database may aid research into the ongoing pandemic.


Assuntos
Betacoronavirus/química , Betacoronavirus/genética , Infecções por Coronavirus/metabolismo , Bases de Dados de Proteínas , Simulação de Dinâmica Molecular , Pneumonia Viral/metabolismo , Proteoma , Sistemas de Transporte de Aminoácidos Neutros/química , Sistemas de Transporte de Aminoácidos Neutros/genética , Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Enzima de Conversão de Angiotensina 2 , População Negra/genética , COVID-19 , Infecções por Coronavirus/virologia , Proteínas do Nucleocapsídeo de Coronavírus , Predisposição Genética para Doença , Variação Genética , Interações Hospedeiro-Patógeno , Humanos , Masculino , Proteínas do Nucleocapsídeo/química , Proteínas do Nucleocapsídeo/metabolismo , Pandemias , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Fosfoproteínas , Pneumonia Viral/virologia , Mapas de Interação de Proteínas , Processamento de Proteína Pós-Traducional , SARS-CoV-2 , Homologia de Sequência de Aminoácidos , Serina Endopeptidases/química , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo
12.
ACS Chem Biol ; 14(9): 2044-2054, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31430120

RESUMO

Nonribosomal peptides are important natural products biosynthesized by nonribosomal peptide synthetases (NRPSs). Adenylation (A) domains of NRPSs are highly specific for the substrate they recognize. This recognition is determined by 10 residues in the substrate-binding pocket, termed the specificity code. This finding led to the proposal that nonribosomal peptides could be altered by specificity code swapping. Unfortunately, this approach has proven, with few exceptions, to be unproductive; changing the specificity code typically results in broadened specificity or poor function. To enhance our understanding of A domain substrate selectivity, we carried out a detailed analysis of the specificity code from the A domain of EntF, an NRPS involved in enterobactin biosynthesis in Escherichia coli. Using directed evolution and a genetic selection, we determined which sites in the code have strict residue requirements and which are tolerant of variation. We showed that the EntF A domain, and other l-Ser-specific A domains, have a functional sequence space for l-Ser recognition, rather than a single code. This functional space is more expansive than the aggregate of all characterized l-Ser-specific A domains: we identified 152 new l-Ser specificity codes. Together, our data provide essential insights into how to overcome the barriers that prevent rational changes to A domain specificity.


Assuntos
Peptídeo Sintases/metabolismo , Motivos de Aminoácidos , Evolução Molecular Direcionada/métodos , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Etilenodiaminas/farmacologia , Quelantes de Ferro/farmacologia , Peptídeo Sintases/química , Peptídeo Sintases/genética , Domínios Proteicos , Serina/química , Especificidade por Substrato
13.
Am Surg ; 85(6): 579-586, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31267897

RESUMO

We aim to investigate the prevalence of posttraumatic stress disorder (PTSD), physician burnout (PBO), and work-life balance (WLB) among surgical residents, fellows, and attendings to illustrate the trends in surgeon wellness. A cross-sectional national survey of surgical residents, fellows, and attendings was conducted screening for PTSD, PBO, and WLB. The prevalence of screening positive for PTSD was more than two times that of the general population at all levels of experience, and more than half have an unhealthy WLB. The prevalence of PTSD, PBO, and unhealthy WLB declined with increasing level of experience (P < 0.001). One deviation in this trend was a lower prevalence of PBO among surgical fellows compared with residents and attendings (P < 0.001). Surgeon wellness improved with increasing level of experience. The incorporation of wellness programs into surgical residencies is essential to the professional development of young surgeons to cultivate healthy lasting habits for a well-balanced career and life.


Assuntos
Esgotamento Profissional/epidemiologia , Promoção da Saúde/organização & administração , Satisfação no Emprego , Satisfação Pessoal , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Cirurgiões/psicologia , Adulto , Esgotamento Profissional/psicologia , Estudos Transversais , Bolsas de Estudo/tendências , Feminino , Humanos , Internato e Residência/tendências , Masculino , Corpo Clínico Hospitalar/tendências , Pessoa de Meia-Idade , Avaliação das Necessidades , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Cirurgiões/educação , Estados Unidos , Adulto Jovem
14.
Metab Eng ; 55: 92-101, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31226347

RESUMO

Common strategies for conversion of lignocellulosic biomass to chemical products center on deconstructing biomass polymers into fermentable sugars. Here, we demonstrate an alternative strategy, a growth-coupled, high-yield bioconversion, by feeding cells a non-sugar substrate, by-passing central metabolism, and linking a key metabolic step to generation of acetyl-CoA that is required for biomass and energy generation. Specifically, we converted levulinic acid (LA), an established degradation product of lignocellulosic biomass, to butanone (a.k.a. methyl-ethyl ketone - MEK), a widely used industrial solvent. Our strategy combines a catabolic pathway from Pseudomonas putida that enables conversion of LA to 3-ketovaleryl-CoA, a CoA transferase that generates 3-ketovalerate and acetyl-CoA, and a decarboxylase that generates 2-butanone. By removing the ability of E. coli to consume LA and supplying excess acetate as a carbon source, we built a strain of E. coli that could convert LA to butanone at high yields, but at the cost of significant acetate consumption. Using flux balance analysis as a guide, we built a strain of E. coli that linked acetate assimilation to production of butanone. This strain was capable of complete bioconversion of LA to butanone with a reduced acetate requirement and increased specific productivity. To demonstrate the bioconversion on real world feedstocks, we produced LA from furfuryl alcohol, a compound readily obtained from biomass. These LA feedstocks were found to contain inhibitors that prevented cell growth and bioconversion of LA to butanone. We used a combination of column chromatography and activated carbon to remove the toxic compounds from the feedstock, resulting in LA that could be completely converted to butanone. This work motivates continued collaboration between chemical and biological catalysis researchers to explore alternative conversion pathways and the technical hurdles that prevent their rapid deployment.


Assuntos
Butanonas/metabolismo , Escherichia coli , Ácidos Levulínicos/metabolismo , Microrganismos Geneticamente Modificados , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Microrganismos Geneticamente Modificados/genética , Microrganismos Geneticamente Modificados/metabolismo , Pseudomonas putida/enzimologia , Pseudomonas putida/genética
15.
Medchemcomm ; 10(5): 668-681, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31191858

RESUMO

Bacteria have historically been a rich source of natural products (e.g. polyketides and non-ribosomal peptides) that possess medically-relevant activities. Despite extensive discovery programs in both industry and academia, a plethora of biosynthetic pathways remain uncharacterized and the corresponding molecular products untested for potential bioactivities. This knowledge gap comes in part from the fact that many putative natural product producers have not been cultured in conventional laboratory settings in which the corresponding products are produced at detectable levels. Next-generation sequencing technologies are further increasing the knowledge gap by obtaining metagenomic sequence information from complex communities where production of the desired compound cannot be isolated in the laboratory. For these reasons, many groups are turning to synthetic biology to produce putative natural products in heterologous hosts. This strategy depends on the ability to heterologously express putative biosynthetic gene clusters and produce relevant quantities of the corresponding products. Actinobacteria remain the most abundant source of natural products and the most promising heterologous hosts for natural product discovery and production. However, researchers are discovering more natural products from other groups of bacteria, such as myxobacteria and cyanobacteria. Therefore, phylogenetically similar heterologous hosts have become promising candidates for synthesizing these novel molecules. The downside of working with these microbes is the lack of well-characterized genetic tools for optimizing expression of gene clusters and product titers. This review examines heterologous expression of natural product gene clusters in terms of the motivations for this research, the traits desired in an ideal host, tools available to the field, and a survey of recent progress.

16.
Am Surg ; 85(2): 127-135, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30819287

RESUMO

Posttraumatic stress disorder (PTSD) among trauma surgeons is three times that of the general population, and physician burnout (PBO) among surgeons is rising. Given that PTSD and PBO are both stress-based syndromes, we aim to identify the prevalence and risk factors for PTSD among trauma and nontrauma surgeons, and determine if a relationship exists. A cross-sectional survey of surgeons was conducted between September 2016 and May 2017. Respondents were screened for PTSD and PBO. Traumatic stressors were identified, and 20 potential risk factors were assessed. The respondents (n = 1026) were grouped into trauma (n = 350) and nontrauma (n = 676). Between the cohorts, there was no significant difference in prevalence of screening positive for PTSD (17% vs 15%) or PBO (30% vs 25%). A relationship was found between PTSD and PBO (P < 0.001). The most common traumatic stressor was overwhelming work responsibilities. Potential risk factors for PTSD differed, but overlapping risk factors included hospital culture, hospital support, and salary (P < 0.05). Our findings of an association between PTSD and PBO is concerning. Interventions to reduce rates of PTSD should target changing the existing culture of surgery, improving hospital support, and ensuring equitable pay.


Assuntos
Esgotamento Profissional/epidemiologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Traumatologia , Adulto , Idoso , Esgotamento Profissional/complicações , Esgotamento Profissional/psicologia , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Satisfação no Emprego , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Salários e Benefícios , Transtornos de Estresse Pós-Traumáticos/complicações , Transtornos de Estresse Pós-Traumáticos/psicologia , Estados Unidos , Carga de Trabalho
17.
J Ind Microbiol Biotechnol ; 45(7): 517-527, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29299733

RESUMO

Pseudomonas putida is a promising bacterial host for producing natural products, such as polyketides and nonribosomal peptides. In these types of projects, researchers need a genetic toolbox consisting of plasmids, characterized promoters, and techniques for rapidly editing the genome. Past reports described constitutive promoter libraries, a suite of broad host range plasmids that replicate in P. putida, and genome-editing methods. To augment those tools, we have characterized a set of inducible promoters and discovered that IPTG-inducible promoter systems have poor dynamic range due to overexpression of the LacI repressor. By replacing the promoter driving lacI expression with weaker promoters, we increased the fold induction of an IPTG-inducible promoter in P. putida KT2440 to 80-fold. Upon discovering that gene expression from a plasmid was unpredictable when using a high-copy mutant of the BBR1 origin, we determined the copy numbers of several broad host range origins and found that plasmid copy numbers are significantly higher in P. putida KT2440 than in the synthetic biology workhorse, Escherichia coli. Lastly, we developed a λRed/Cas9 recombineering method in P. putida KT2440 using the genetic tools that we characterized. This method enabled the creation of scarless mutations without the need for performing classic two-step integration and marker removal protocols that depend on selection and counterselection genes. With the method, we generated four scarless deletions, three of which we were unable to create using a previously established genome-editing technique.


Assuntos
Proteínas de Bactérias/biossíntese , Edição de Genes/métodos , Regulação Bacteriana da Expressão Gênica , Pseudomonas putida/genética , Biologia Sintética/métodos , Escherichia coli/genética , Plasmídeos/genética , Plasmídeos/metabolismo , Regiões Promotoras Genéticas/genética , Pseudomonas putida/metabolismo
18.
Am J Surg ; 214(6): 1118-1124, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28987413

RESUMO

BACKGROUND: We aim to evaluate the prevalence of PTSD, its association with physician burnout, and risk factors for PTSD among surgical residents. METHODS: A cross-sectional national survey of surgical residents was conducted screening for PTSD. Causative traumatic stressors were queried, and thirty-one potential risk factors for PTSD were evaluated. RESULTS: A positive PTSD screen (PTSD+) was found in 22% of 582 surgical residents, and an additional 35% were "at risk" for PTSD. Traumatic experiences occurred most commonly as a PGY1, and the most common stressor was bullying. An increase in average hours of work per week (p < 0.001), a high-risk screen for PBO (p < 0.001), and feeling unhealthy (p = 0.001) were associated with an increasing prevalence of screening PTSD+. CONCLUSIONS: The prevalence of screening PTSD+ among surgical residents (22%) was more than three times the general population. Increased work-hours, a high-risk PBO screen, and reduced resident wellness were associated with screening PTSD+.


Assuntos
Esgotamento Profissional/etiologia , Esgotamento Profissional/psicologia , Cirurgia Geral/educação , Internato e Residência , Médicos/psicologia , Transtornos de Estresse Pós-Traumáticos/etiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Adulto , Bullying , Esgotamento Profissional/epidemiologia , Estudos Transversais , Feminino , Nível de Saúde , Humanos , Masculino , Prevalência , Fatores de Risco , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Inquéritos e Questionários , Estados Unidos/epidemiologia , Carga de Trabalho
20.
ISRN Ophthalmol ; 2014: 950975, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24734198

RESUMO

Purpose. To evaluate our community-based institutional experience with plaque brachytherapy for uveal melanomas with a focus on local control rates, factors impacting disease progression, and dosimetric parameters impacting treatment toxicity. Methods and Materials. Our institution was retrospectively reviewed from 1996 to 2011; all patients who underwent plaque brachytherapy for uveal melanoma were included. Follow-up data were collected regarding local control, distant metastases, and side effects from treatment. Analysis was performed on factors impacting treatment outcomes and treatment toxicity. Results. A total of 107 patients underwent plaque brachytherapy, of which 88 had follow-up data available. Local control at 10 years was 94%. Freedom from progression (FFP) and overall survival at 10 years were 83% and 79%, respectively. On univariate analysis, there were no tumor or dosimetric treatment characteristics that were found to have a prognostic impact on FFP. Brachytherapy treatment was well tolerated, with clinically useful vision (>20/200) maintained in 64% of patients. Statistically significant dosimetric relationships were established with cataract, glaucoma, and retinopathy development (greatest P = 0.05). Conclusions. Treatment with plaque brachytherapy demonstrates excellent outcomes in a community-based setting. It is well tolerated and should remain a standard of care for COMS medium sized tumors.

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