RESUMEN
BACKGROUND: The basidiomycete fungus Moniliophthora perniciosa is the causal agent of Witches' Broom Disease (WBD) in cacao (Theobroma cacao). It is a hemibiotrophic pathogen that colonizes the apoplast of cacao's meristematic tissues as a biotrophic pathogen, switching to a saprotrophic lifestyle during later stages of infection. M. perniciosa, together with the related species M. roreri, are pathogens of aerial parts of the plant, an uncommon characteristic in the order Agaricales. A genome survey (1.9x coverage) of M. perniciosa was analyzed to evaluate the overall gene content of this phytopathogen. RESULTS: Genes encoding proteins involved in retrotransposition, reactive oxygen species (ROS) resistance, drug efflux transport and cell wall degradation were identified. The great number of genes encoding cytochrome P450 monooxygenases (1.15% of gene models) indicates that M. perniciosa has a great potential for detoxification, production of toxins and hormones; which may confer a high adaptive ability to the fungus. We have also discovered new genes encoding putative secreted polypeptides rich in cysteine, as well as genes related to methylotrophy and plant hormone biosynthesis (gibberellin and auxin). Analysis of gene families indicated that M. perniciosa have similar amounts of carboxylesterases and repertoires of plant cell wall degrading enzymes as other hemibiotrophic fungi. In addition, an approach for normalization of gene family data using incomplete genome data was developed and applied in M. perniciosa genome survey. CONCLUSION: This genome survey gives an overview of the M. perniciosa genome, and reveals that a significant portion is involved in stress adaptation and plant necrosis, two necessary characteristics for a hemibiotrophic fungus to fulfill its infection cycle. Our analysis provides new evidence revealing potential adaptive traits that may play major roles in the mechanisms of pathogenicity in the M. perniciosa/cacao pathosystem.
Asunto(s)
Agaricales/genética , Cacao/microbiología , Genoma Fúngico , Enfermedades de las Plantas/microbiología , Agaricales/patogenicidad , Análisis por Conglomerados , ADN de Hongos/genética , Etiquetas de Secuencia Expresada , Genes Fúngicos , Genómica , Modelos Genéticos , Familia de Multigenes , Alineación de Secuencia , Análisis de Secuencia de ADNRESUMEN
Sickle cell anaemia (SCA) patients have a high risk of infection. We retrospectively investigated the prevalence of infection among SCA patients from Bahia, Brazil. A total of 1415 SCA patients were studied between 1995 and 2009: 190 (13.4%) had hepatitis C virus (HCV), 67 (4.7%) had human T-lymphotropic virus type I (HTLV-I), 44 (3.1%) had hepatitis B virus (HBV), 40 (2.8%) had Chagas' disease, 11 (0.8%) had human immunodeficiency virus (HIV), and 5 (0.4%) had syphilis. Patients with HCV infection had a higher risk of hospitalisation (OR=1.52, 95% Cl: 1.07-2.17, P=0.020), bone disorders (OR=1.94, 95% Cl: 1.15-3.27, P=0.011), stroke (OR=2.17, 95% Cl: 1.12-4.14, P=0.017), painful crisis (OR=1.61, 95% Cl: 1.17-2.22, P=0.004) and leg ulcers (OR=1.61, 95% Cl: 1.04-3.03, P=0.031). Patients with HBV infection had a higher risk for bone disorders (OR=4.90, 95% Cl: 2.08-11.54, P<.010), stroke (OR=3.01, 95% Cl: 1.29-6.04, P=0.007), painful crisis (OR=3.51, 95% Cl: 1.62-7.63, P<0.001), acute chest syndrome (ACS) (OR=2.66, 95% Cl: 1.34-5.28, P=0.004), leg ulcers (OR=6.60, 95% Cl: 3.37-12.91, P<.001) and vaso-occlusive crisis (OR=6.34, 95% Cl: 1.96-20.66, P<0.001). Patients with HTLV-I infection had a high risk for bone disorders (OR=2.94, 95% Cl: 1.28-6.74, P=0.011), respiratory failure (OR=2.66, 95% Cl: 1.26-5.51, P=0.012), leg ulcers (OR=3.27, 95% Cl: 1.69-6.11, P<.001), painful crisis (OR=1.82, 95% Cl: 1.07-3.13, P=0.025) and ACS (OR=1.85, 95% Cl: 1.10-3.41, P<.047). SCA patients with HCV infection had increased triglycerides and low-density lipoprotein cholesterol (P=0.036; P=0.027), iron serum (P=0.016) and ferritin (P=0.007). These results reveal important roles for these infections in SCA patients' clinical outcomes, and studies are warranted to determine the mechanisms utilised by these agents and their involvement in disease severity.