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1.
J Marital Fam Ther ; 49(3): 595-612, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37036303

RESUMO

Many aspects of systemic family therapist (SFT) training and competence play a vital role in effective treatment and professional satisfaction. One area that has been significantly overlooked by many SFTs is the role of psychotropic medication (PM) in conjunction with talk therapy for optimal mental health outcomes. This study explores the current status of PM in SFT training and clinical practice. Our findings highlight the continued struggle of SFTs in their comfort level with addressing the PM needs of their clients. We identified a perceived inadequacy of SFT training and supervision regarding PM use. SFTs around the world need to find educational opportunities to improve their competence in working with their clients and their prescribed medications. Additional studies need to be conducted on strategies and mechanisms to improve client care. If SFTs are ignorant of PM, their treatment of clients-who often use PM-will be compromised.


Assuntos
Psicofarmacologia , Febre Grave com Síndrome de Trombocitopenia , Humanos , Atitude do Pessoal de Saúde
2.
J Sex Marital Ther ; 48(7): 663-679, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35240952

RESUMO

This study presents the second part of a mixed methods exploration of couple sexual communication. The purpose of this study was to better understand the sexual communication processes that characterize various couple typologies. A qualitative content analysis was used to examine the responses of couples who were grouped together according to the typologies developed from the cluster analysis conducted in Part I of this study (Jones & Lucero Jones, 2022). The results revealed 3 primary themes regarding sexual communication: sexual communication behaviors, sexual decision-making processes, and sexual communication outcomes. Most importantly, the 15 subthemes revealed the inner workings of sexual communication in couples of varying typologies. Clinicians may use the findings from this study to recognize communication patterns in couples that may be contributing to sexual dissatisfaction. Furthermore, the study highlights critical sexual communication behaviors and patterns for improvement and connection in the sexual relationship.


Assuntos
Comportamento Sexual , Parceiros Sexuais , Comunicação , Emoções , Humanos
3.
J Sex Marital Ther ; 48(6): 593-606, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35282791

RESUMO

This study presents the first part of a mixed-methods exploration of couple sexual communication. Typologies of heterosexual couples in committed, sexual relationships were created for further exploration of group differences in sexual communication. A cluster analysis categorized couples into four different couple typologies: mutually satisfied, satisfied men/dissatisfied women, satisfied women/dissatisfied men, and mutually dissatisfied. Using a MANOVA approach, the couple typologies were used to identify differences in how the couple types communicated about sex. The results revealed significant differences among the differing couple types, which will be explored qualitatively in part two of this analysis.


Assuntos
Comportamento Sexual , Parceiros Sexuais , Análise por Conglomerados , Comunicação , Feminino , Heterossexualidade , Humanos , Masculino
4.
South Med J ; 114(5): 277-282, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33942111

RESUMO

OBJECTIVE: Recognition and reporting of vector-borne and zoonotic disease (VBZD) cases is largely dependent upon the consideration of such diseases by healthcare practitioners during the initial diagnosis and ordering of specific confirmative diagnostic tests. This study was conducted to assess the general knowledge and understanding of VBZD transmission and clinical presentation. METHODS: Healthcare practitioners were surveyed to determine the extent of training and educational experiences they received relative to VBZDs, and their likelihood to consider such diseases during differential diagnoses. In addition, an assessment of their knowledge of arthropod species that may transmit VBZD pathogens was conducted. RESULTS: Having postprofessional school training relevant to VBZDs significantly influenced diagnostic accuracy for such disease cases based on the presented clinical signs and symptoms. CONCLUSIONS: The prevalence of VBZDs in the United States likely is significantly underestimated. The authors suggest the enhancement of VBZD-focused education as an important initiative that would significantly improve timely diagnosis, treatment, and, ultimately, prevention of these diseases.


Assuntos
Doenças Transmitidas por Vetores/diagnóstico , Zoonoses/diagnóstico , Animais , Diagnóstico Diferencial , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Inquéritos e Questionários , Estados Unidos
5.
mBio ; 10(2)2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30837337

RESUMO

Terrestrial fungi play critical roles in nutrient cycling and food webs and can shape macroorganism communities as parasites and mutualists. Although estimates for the number of fungal species on the planet range from 1.5 to over 5 million, likely fewer than 10% of fungi have been identified so far. To date, a relatively small percentage of described species are associated with marine environments, with ∼1,100 species retrieved exclusively from the marine environment. Nevertheless, fungi have been found in nearly every marine habitat explored, from the surface of the ocean to kilometers below ocean sediments. Fungi are hypothesized to contribute to phytoplankton population cycles and the biological carbon pump and are active in the chemistry of marine sediments. Many fungi have been identified as commensals or pathogens of marine animals (e.g., corals and sponges), plants, and algae. Despite their varied roles, remarkably little is known about the diversity of this major branch of eukaryotic life in marine ecosystems or their ecological functions. This perspective emerges from a Marine Fungi Workshop held in May 2018 at the Marine Biological Laboratory in Woods Hole, MA. We present the state of knowledge as well as the multitude of open questions regarding the diversity and function of fungi in the marine biosphere and geochemical cycles.


Assuntos
Organismos Aquáticos/classificação , Organismos Aquáticos/isolamento & purificação , Biodiversidade , Fungos/classificação , Fungos/isolamento & purificação , Sedimentos Geológicos/microbiologia , Água do Mar/microbiologia
6.
J Marital Fam Ther ; 45(2): 275-295, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30009425

RESUMO

The ability to conceptualize and treat sexual problems has been widely accepted as a crucial skill to master the MFT training. However, clients' sexual relationships are often ignored by clinicians because of a lack of experience or training, or personal discomfort. In this content analysis, we review sex and sex therapy research within MFT and family studies journals since the turn of the century. Of the 13,919 articles published within the 15 journals, 137 focused on sexuality or sex therapy. The articles were divided into five themes: sexual and relational health, sexual diversity, treatment and contributors of sexual dysfunction, sex therapy practices, and sexual education and development. Implications for clinical practices, sex therapy integration, and future research are discussed.


Assuntos
Bibliometria , Pesquisa Biomédica/estatística & dados numéricos , Terapia Familiar/estatística & dados numéricos , Terapia Conjugal/estatística & dados numéricos , Comportamento Sexual , Disfunções Sexuais Psicogênicas/terapia , Terapia Familiar/educação , Humanos , Terapia Conjugal/educação
7.
PLoS Biol ; 16(7): e2006333, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29965960

RESUMO

Our current understanding of biology is heavily based on a small number of genetically tractable model organisms. Most eukaryotic phyla lack such experimental models, and this limits our ability to explore the molecular mechanisms that ultimately define their biology, ecology, and diversity. In particular, marine protists suffer from a paucity of model organisms despite playing critical roles in global nutrient cycles, food webs, and climate. To address this deficit, an initiative was launched in 2015 to foster the development of ecologically and taxonomically diverse marine protist genetic models. The development of new models faces many barriers, some technical and others institutional, and this often discourages the risky, long-term effort that may be required. To lower these barriers and tackle the complexity of this effort, a highly collaborative community-based approach was taken. Herein, we describe this approach, the advances achieved, and the lessons learned by participants in this novel community-based model for research.


Assuntos
Comportamento Cooperativo , Modelos Teóricos , Organismos Aquáticos/fisiologia , Eucariotos/classificação , Filogenia , Transformação Genética
8.
J Marital Fam Ther ; 44(4): 606-623, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29044661

RESUMO

In a study of 142 couples, we gathered survey data to show how sexual communication influences sexual and relationship satisfaction as well as sexual and orgasm frequency. In two dyadic data path analyses, we observed the significant paths of influence that sexual communication has on sexual and relationship satisfaction, as well as sexual and orgasm frequency. Our findings revealed greater amounts of sexual communication were associated with increased orgasm frequency in women and greater relationship and sexual satisfaction in both sexes. We also observed important differences in the associations of sexual communication and general communication on satisfaction levels. With these analyses, we expand the current literature to broaden our understanding of the role that sexual communication plays in committed relationships.


Assuntos
Comunicação , Relações Interpessoais , Orgasmo , Satisfação Pessoal , Comportamento Sexual/psicologia , Parceiros Sexuais/psicologia , Cônjuges/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
RNA Biol ; 14(11): 1617-1626, 2017 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-28665778

RESUMO

FK506 (tacrolimus) is a valuable immunosuppressant produced by several Streptomyces strains. In the genome of the wild type producer Streptomyces tsukubaensis NRRL18488, FK506 biosynthesis is encoded by a gene cluster that spans 83.5 (kb). A whole transcriptome differential shotgun sequencing (dRNA-seq) of S. tsukubaensis was performed to analyze transcription at 2 different time points; before and during active FK506 production. In total, 8,914 transcription start sites were identified in either condition, which enabled precise determination of the 5'-UTR length of the corresponding transcripts as well as the identification of 2 consensus sequence motifs in the promoter regions. The transcription start sites of all gene operons within the FK506 cluster were identified, including 3 examples of leaderless RNA transcripts. These data provide detailed insight into the transcription of the FK506 biosynthetic gene cluster to support future regulatory studies, genetic manipulation, and industrial production.


Assuntos
Proteínas de Bactérias/genética , DNA Bacteriano/genética , Regulação Bacteriana da Expressão Gênica , Streptomyces/genética , Tacrolimo/metabolismo , Transcriptoma , Regiões 5' não Traduzidas , Proteínas de Bactérias/metabolismo , Sequência de Bases , DNA Bacteriano/metabolismo , Perfilação da Expressão Gênica , Biblioteca Gênica , Família Multigênica , Óperon , Regiões Promotoras Genéticas , Análise de Sequência de DNA , Streptomyces/metabolismo , Sítio de Iniciação de Transcrição
10.
Nat Chem Biol ; 11(9): 625-31, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26284661
11.
PLoS One ; 8(7): e69319, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23874942

RESUMO

We describe a procedure for the conjugative transfer of phage P1-derived Artificial Chromosome (PAC) library clones containing large natural product gene clusters (≥70 kilobases) to Streptomyces coelicolor strains that have been engineered for improved heterologous production of natural products. This approach is demonstrated using the gene cluster for FK506 (tacrolimus), a clinically important immunosuppressant of high commercial value. The entire 83.5 kb FK506 gene cluster from Streptomyces tsukubaensis NRRL 18488 present in one 130 kb PAC clone was introduced into four different S. coelicolor derivatives and all produced FK506 and smaller amounts of the related compound FK520. FK506 yields were increased by approximately five-fold (from 1.2 mg L(-1) to 5.5 mg L(-1)) in S. coelicolor M1146 containing the FK506 PAC upon over-expression of the FK506 LuxR regulatory gene fkbN. The PAC-based gene cluster conjugation methodology described here provides a tractable means to evaluate and manipulate FK506 biosynthesis and is readily applicable to other large gene clusters encoding natural products of interest to medicine, agriculture and biotechnology.


Assuntos
Bacteriófagos/genética , Bacteriófagos/metabolismo , Cromossomos Artificiais de Bacteriófago P1 , Imunossupressores/metabolismo , Família Multigênica , Tacrolimo/metabolismo , Regulação Bacteriana da Expressão Gênica , Genes Reguladores , Streptomyces/genética , Streptomyces/metabolismo
12.
FEBS J ; 279(7): 1243-51, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22314229

RESUMO

Filamentous marine cyanobacteria are extremely rich sources of bioactive natural products and often employ highly unusual biosynthetic enzymes in their assembly. However, the current lack of techniques for stable DNA transfer into these filamentous organisms, combined with the absence of heterologous expression strategies for nonribosomal cyanobacterial gene clusters, prohibit the creation of mutant strains or the heterologous production of these cyanobacterial compounds in other bacteria. In this study, we evaluated the capability of a derivative of the model actinomycete Streptomyces coelicolor A3(2) to express enzymes involved in the biosynthesis of the protein kinase C activator lyngbyatoxin A from a Hawaiian strain of Moorea producta (previously classified as Lyngbya majuscula). Despite large differences in GC content between these two bacteria and the presence of rare TTA/UUA leucine codons in lyngbyatoxin ORFs we were able to achieve expression of the cytochrome P450 monooxygenase LtxB and reverse prenyltransferase LtxC in S. coelicolor M512 and confirmed the in vitro functionality of S. coelicolor overexpressed LtxC. Attempts to express the entire lyngbyatoxin A gene cluster in S. coelicolor M512 were not successful because of transcript termination observed for the ltxA gene, which encodes a large nonribosomal peptide synthetase. However, these attempts did show a detectable level of cyanobacterial promoter recognition in Streptomyces. Successful expression of lyngbyatoxin A proteins in Streptomyces provides a new platform for biochemical investigation of natural product enzymes from Moorea strains.


Assuntos
Proteínas de Bactérias/metabolismo , Cianobactérias/genética , Cianobactérias/metabolismo , Toxinas de Lyngbya/metabolismo , Proteína Quinase C/metabolismo , Streptomyces coelicolor/genética , Streptomyces coelicolor/metabolismo , Proteínas de Bactérias/genética , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Cianobactérias/química , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Toxinas de Lyngbya/química , Estrutura Molecular , Família Multigênica , Fases de Leitura Aberta , Proteína Quinase C/genética
13.
Proc Natl Acad Sci U S A ; 108(21): 8815-20, 2011 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-21555588

RESUMO

Filamentous cyanobacteria of the genus Lyngbya are important contributors to coral reef ecosystems, occasionally forming dominant cover and impacting the health of many other co-occurring organisms. Moreover, they are extraordinarily rich sources of bioactive secondary metabolites, with 35% of all reported cyanobacterial natural products deriving from this single pantropical genus. However, the true natural product potential and life strategies of Lyngbya strains are poorly understood because of phylogenetic ambiguity, lack of genomic information, and their close associations with heterotrophic bacteria and other cyanobacteria. To gauge the natural product potential of Lyngbya and gain insights into potential microbial interactions, we sequenced the genome of Lyngbya majuscula 3L, a Caribbean strain that produces the tubulin polymerization inhibitor curacin A and the molluscicide barbamide, using a combination of Sanger and 454 sequencing approaches. Whereas ∼ 293,000 nucleotides of the draft genome are putatively dedicated to secondary metabolism, this is far too few to encode a large suite of Lyngbya metabolites, suggesting Lyngbya metabolites are strain specific and may be useful in species delineation. Our analysis revealed a complex gene regulatory network, including a large number of sigma factors and other regulatory proteins, indicating an enhanced ability for environmental adaptation or microbial associations. Although Lyngbya species are reported to fix nitrogen, nitrogenase genes were not found in the genome or by PCR of genomic DNA. Subsequent growth experiments confirmed that L. majuscula 3L is unable to fix atmospheric nitrogen. These unanticipated life history characteristics challenge current views of the genus Lyngbya.


Assuntos
Cianobactérias/genética , Cianobactérias/fisiologia , Redes Reguladoras de Genes , Genoma Bacteriano/genética , Ciclopropanos , Ecologia , Genes Bacterianos/fisiologia , Biologia Marinha , Fixação de Nitrogênio/genética , Análise de Sequência de DNA , Tiazóis
14.
Appl Environ Microbiol ; 77(11): 3617-25, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21498757

RESUMO

Bacteria of the genus Frankia are mycelium-forming actinomycetes that are found as nitrogen-fixing facultative symbionts of actinorhizal plants. Although soil-dwelling actinomycetes are well-known producers of bioactive compounds, the genus Frankia has largely gone uninvestigated for this potential. Bioinformatic analysis of the genome sequences of Frankia strains ACN14a, CcI3, and EAN1pec revealed an unexpected number of secondary metabolic biosynthesis gene clusters. Our analysis led to the identification of at least 65 biosynthetic gene clusters, the vast majority of which appear to be unique and for which products have not been observed or characterized. More than 25 secondary metabolite structures or structure fragments were predicted, and these are expected to include cyclic peptides, siderophores, pigments, signaling molecules, and specialized lipids. Outside the hopanoid gene locus, no cluster could be convincingly demonstrated to be responsible for the few secondary metabolites previously isolated from other Frankia strains. Few clusters were shared among the three species, demonstrating species-specific biosynthetic diversity. Proteomic analysis of Frankia sp. strains CcI3 and EAN1pec showed that significant and diverse secondary metabolic activity was expressed in laboratory cultures. In addition, several prominent signals in the mass range of peptide natural products were observed in Frankia sp. CcI3 by intact-cell matrix-assisted laser desorption-ionization mass spectrometry (MALDI-MS). This work supports the value of bioinformatic investigation in natural products biosynthesis using genomic information and presents a clear roadmap for natural products discovery in the Frankia genus.


Assuntos
Produtos Biológicos/biossíntese , Vias Biossintéticas/genética , Frankia/genética , Frankia/metabolismo , Genômica , Proteômica , Família Multigênica
15.
Proc Natl Acad Sci U S A ; 108(13): 5226-31, 2011 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-21393570

RESUMO

Sessile marine organisms are prolific sources of biologically active natural products. However, these compounds are often found in highly variable amounts, with the abiotic and biotic factors governing their production remaining poorly understood. We present an approach that permits monitoring of in vivo natural product production and turnover using mass spectrometry and stable isotope ((15)N) feeding with small cultures of various marine strains of the natural product-rich cyanobacterial genus Lyngbya. This temporal comparison of the amount of in vivo (15)N labeling of nitrogen-containing metabolites represents a direct way to discover and evaluate factors influencing natural product biosynthesis, as well as the timing of specific steps in metabolite assembly, and is a strong complement to more traditional in vitro studies. Relative quantification of (15)N labeling allowed the concurrent measurement of turnover rates of multiple natural products from small amounts of biomass. This technique also afforded the production of the neurotoxic jamaicamides to be more carefully studied, including an assessment of how jamaicamide turnover compares with filament growth rate and primary metabolism and provided new insights into the biosynthetic timing of jamaicamide A bromination. This approach should be valuable in determining how environmental factors affect secondary metabolite production, ultimately yielding insight into the energetic balance among growth, primary production, and secondary metabolism, and thus aid in the development of methods to improve compound yields for biomedical or biotechnological applications.


Assuntos
Produtos Biológicos/biossíntese , Cianobactérias/metabolismo , Água do Mar/microbiologia , Amidas/química , Amidas/metabolismo , Produtos Biológicos/química , Biomassa , Cianobactérias/fisiologia , Lipopeptídeos/química , Lipopeptídeos/metabolismo , Metaboloma , Estrutura Molecular , Isótopos de Nitrogênio/metabolismo , Feofitinas/química , Feofitinas/metabolismo , Pirrolidinonas/química , Pirrolidinonas/metabolismo
16.
Chem Biol ; 18(3): 281-3, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21439471

RESUMO

Hormaomycin, an NRPS-produced bacterial metabolite involved in microbial signaling, possesses several remarkable structural features. The study by Höfer et al. (2011) employed a range of methodologies to explore and ultimately understand the elaborate biosynthesis of this complex natural product.

17.
Nat Prod Rep ; 27(7): 1048-65, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20442916

RESUMO

Cyanobacteria are abundant producers of natural products well recognized for their bioactivity and utility in drug discovery and biotechnology applications. In the last decade, characterization of several modular gene clusters that code for the biosynthesis of these compounds has revealed a number of unusual enzymatic reactions. In this article, we review several mechanistic transformations identified in marine cyanobacterial biosynthetic pathways, with an emphasis on modular polyketide synthase(PKS)/non-ribosomal peptide synthetase (NRPS) gene clusters. In selected instances, we also make comparisons between cyanobacterial gene clusters derived from marine and freshwater strains. We then provide an overview of recent developments in cyanobacterial natural products biosynthesis made available through genome sequencing and new advances in bioinformatics and genetics.


Assuntos
Produtos Biológicos , Cianobactérias , Biologia Marinha , Produtos Biológicos/biossíntese , Produtos Biológicos/química , Cianobactérias/química , Cianobactérias/genética , Cianobactérias/metabolismo , Estrutura Molecular , Peptídeo Sintases/metabolismo , Policetídeo Sintases/metabolismo
18.
BMC Microbiol ; 9: 247, 2009 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19951434

RESUMO

BACKGROUND: The marine cyanobacterium Lyngbya majuscula is a prolific producer of bioactive secondary metabolites. Although biosynthetic gene clusters encoding several of these compounds have been identified, little is known about how these clusters of genes are transcribed or regulated, and techniques targeting genetic manipulation in Lyngbya strains have not yet been developed. We conducted transcriptional analyses of the jamaicamide gene cluster from a Jamaican strain of Lyngbya majuscula, and isolated proteins that could be involved in jamaicamide regulation. RESULTS: An unusually long untranslated leader region of approximately 840 bp is located between the jamaicamide transcription start site (TSS) and gene cluster start codon. All of the intergenic regions between the pathway ORFs were transcribed into RNA in RT-PCR experiments; however, a promoter prediction program indicated the possible presence of promoters in multiple intergenic regions. Because the functionality of these promoters could not be verified in vivo, we used a reporter gene assay in E. coli to show that several of these intergenic regions, as well as the primary promoter preceding the TSS, are capable of driving beta-galactosidase production. A protein pulldown assay was also used to isolate proteins that may regulate the jamaicamide pathway. Pulldown experiments using the intergenic region upstream of jamA as a DNA probe isolated two proteins that were identified by LC-MS/MS. By BLAST analysis, one of these had close sequence identity to a regulatory protein in another cyanobacterial species. Protein comparisons suggest a possible correlation between secondary metabolism regulation and light dependent complementary chromatic adaptation. Electromobility shift assays were used to evaluate binding of the recombinant proteins to the jamaicamide promoter region. CONCLUSION: Insights into natural product regulation in cyanobacteria are of significant value to drug discovery and biotechnology. To our knowledge, this is the first attempt to characterize the transcription and regulation of secondary metabolism in a marine cyanobacterium. If jamaicamide is light regulated, this mechanism would be similar to other cyanobacterial natural product gene clusters such as microcystin LR. These findings could aid in understanding and potentially assisting the management of toxin production by Lyngbya in the environment.


Assuntos
Cianobactérias/genética , Lipopeptídeos/biossíntese , Família Multigênica , Sítio de Iniciação de Transcrição , Amidas , Proteínas de Bactérias/genética , Sequência de Bases , Cianobactérias/metabolismo , DNA Intergênico/genética , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Genes Reporter , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Pirrolidinonas , RNA Bacteriano/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Fatores de Transcrição/genética , Transcrição Gênica
19.
Curr Opin Chem Biol ; 13(2): 216-23, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19307147

RESUMO

Cyanobacteria, among Earth's oldest organisms, have evolved sophisticated biosynthetic pathways to produce a rich arsenal of bioactive natural products. In consequence, cyanobacterial secondary metabolites have been an incredibly fruitful source of lead compounds in drug discovery efforts. Investigations into the biochemistry responsible for the creation of these compounds, complemented by genome sequencing efforts, are revealing unique enzymatic mechanisms not described or rarely described elsewhere in the natural world. Herein, we discuss recent advances in understanding the biosynthesis of three cyanobacterial classes of natural product: mixed polyketide synthase/non ribosomal peptide synthetase (PKS/NRPS) metabolites, aromatic amino acid-derived alkaloids, and ribosomally encoded cyclic peptides. The unique biosynthetic mechanisms employed by cyanobacteria are inspiring new developments in heterologous gene expression and biotechnology.


Assuntos
Produtos Biológicos/biossíntese , Cianobactérias/metabolismo , Eucariotos/metabolismo , Água do Mar/microbiologia , Animais , Oceanos e Mares
20.
Environ Sci Technol ; 41(10): 3728-33, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17547204

RESUMO

The transport and discharge of ship ballast water has been recognized as a major vector for the introduction of invasive species. Chemical oxidants, long used in drinking water and wastewater treatment, are alternative treatment methods for the control of invasive species currently being tested for use on ships. One concern when a ballasted vessel arrives in port is the adverse effects of residual oxidant in the treated water. The most common oxidants include chlorine (HOCl/OCl-), bromine (HOBr/OBr-), ozone (03), hydrogen peroxide (H2O2), chlorine dioxide (ClO2), and monochloramine (NH2Cl). The present study was undertaken to evaluate the sunlight-mediated photochemical decomposition of these oxidants. Sunlight photodecomposition was measured at various pH using either distilled water or oligotrophic Gulf Stream water for specific oxidants. For selected oxidants, quantum yields at specific wavelengths were obtained. An environmental photochemical model, GCSOLAR, also provided predictions of the fate (sunlight photolysis half-lives) of HOCI/OCl-, HOBr/OBr-, ClO2, and NH2Cl for two different seasons at latitude 40 degrees and in water with two different concentrations of chromophoric dissolved organic matter. These data are useful in assessing the environmental fate of ballast water treatment oxidants if they were to be discharged in port.


Assuntos
Oxidantes/química , Fotólise , Navios , Luz Solar , Purificação da Água , Água/química , Absorção , Soluções Tampão , Meia-Vida , Concentração de Íons de Hidrogênio , Cinética , Teoria Quântica , Estações do Ano
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