RESUMO
Four closely related peptides were isolated from seed of Impatiens balsamina and were shown to be inhibitory to the growth of a range of fungi and bacteria, while not being cytotoxic to cultured human cells. The peptides, designated Ib-AMP1, Ib-AMP2, Ib-AMP3, and Ib-AMP4, are 20 amino acids long and are the smallest plant-derived antimicrobial peptides isolated to date. The Ib-AMPs (I. balsamina antimicrobial peptides) are highly basic and contain four cysteine residues which form two intramolecular disulfide bonds. Searches of protein data bases have failed to identify any proteins with significant homology to the peptides described here. Characterization of isolated cDNAs reveals that all four peptides are encoded within a single transcript. The predicted Ib-AMP precursor protein consists of a prepeptide followed by 6 mature peptide domains, each flanked by propeptide domains ranging from 16 to 35 amino acids in length. Such a primary structure with repeated alternating basic mature peptide domains and acidic propeptide domains has, to date, not been reported in plants.
Assuntos
Antibacterianos/isolamento & purificação , Cisteína/análise , Proteínas de Plantas/isolamento & purificação , Plantas/química , Sementes/química , Sequência de Aminoácidos , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Sequência de Bases , Células Cultivadas , DNA Complementar , Eletroforese em Gel de Poliacrilamida , Eritrócitos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/farmacologia , Alinhamento de SequênciaRESUMO
From seeds of Aesculus hippocastanum, Clitoria ternatea, Dahlia merckii and Heuchera sanguinea five antifungal proteins were isolated and shown to be homologous to plant defensins previously characterised from radish seeds and gamma-thionins from Poaceae seeds. Based on the spectrum of their antimicrobial activity and the morphological distortions they induce on fungi the peptides can be divided into two classes. The peptides did not inhibit any of three different alpha-amylases.
Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/farmacologia , Plantas Medicinais/química , Sequência de Aminoácidos , Cálcio/farmacologia , Fungos/efeitos dos fármacos , Magnésio/farmacologia , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Proteínas de Plantas/genética , Sementes/química , Alinhamento de Sequência , Análise de Sequência , Homologia de Sequência de Aminoácidos , Esporos Fúngicos/efeitos dos fármacos , Temperatura , alfa-Amilases/antagonistas & inibidoresRESUMO
One hundred three women who were randomized to receive either routine nursing care (controls) or routine care plus one-to-one support by an experienced monitrice (experimental) were compared as to obstetric outcomes and their memories of types of support they had from nurse, monitrice, and mate. Women assigned a monitrice arrived at the hospital significantly further along in labor, and nearly twice as many had no medication during labor and delivery. Significantly fewer of these women used stirrups during delivery, and more had intact perineums. There was no difference between groups in use of forceps or cesarean sections. Length of labor was confounded by use of medications. Mothers in the experimental group remembered receiving more physical comfort measures, emotional support, and advocacy from monitrices compared to control mothers who received intrapartum care from nurses.