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Cryptococcus gattii is a primary pathogenic fungus that causes pneumonia. This species is also responsible for an outbreak in Vancouver, Canada, and spreading to the mainland and United States. The use of medical devices is often complicated by infections with biofilm-forming microbes with increased resistance to antimicrobial agents and host defense mechanisms. This study investigated the comparative proteome of C. gattii R265 (VGIIa) grown under planktonic and biofilm conditions. A brief comparison with C. neoformans H99 biofilm and the use of different culture medium and surface were also evaluated. Using Multidimensional Protein Identification Technology (MudPIT), 1819 proteins were identified for both conditions, where 150 (8.2%) were considered differentially regulated (up- or down-regulated and unique in biofilm cells). Overall, the proteomic approach suggests that C. gattii R265 biofilm cells are maintained by the induction of electron transport chain for reoxidation, and by alternative energy metabolites, such as succinate and acetate. Since C. gattii is considered a primary pathogen and is one of the most virulent and less susceptible to antifungals, understanding how biofilms are maintained is fundamental to search for new targets to control this important mode of growth that is difficult to eradicate. [Display omitted] • A comparative proteome analysis of C. gattii biofilm was made against planktonic cells. • Metabolic alterations were observed in biofilm, with down-regulation of carbohydrate metabolism. • The electron transport chain seems to be activated in C. gattii biofilm. • Succinate and acetate might support cell maintenance in biofilm. [ABSTRACT FROM AUTHOR]

The increasing demand for high quality and safe food led to important technological innovations in food processing. Cold plasma appears as an emerging technology that has demonstrated efficiency in the removal of microbial contamination from fresh and minimally processed food. In this study, the proteomic profile of Salmonella Enteritidis SE86 subjected to cold plasma treatment was investigated. The number of viable S. Enteritidis SE86 cells was analyzed at different time intervals upon exposure to cold plasma and approximately 100 μg of S. Enteritidis SE86 protein extracts were analyzed by Multidimensional Protein Identification Technology (MudPIT). The results demonstrated that no significant changes in cell counts were detected for up to 20 min exposure to cold plasma, and 2 log reduction was achieved after 60 min. Overall, 1096 proteins were identified, with 249 detected only in plasma-treated samples, and 9 exclusive in non-treated control samples. The proteins uniquely detected in cold plasma-treated cells that showed higher abundance were glyoxalase I, ABC transporter substrate-binding protein and transcriptional activator OsmE, followed by some oxidoreductases. Proteins related with carbohydrate and nucleotide metabolism were mostly overexpressed in cold plasma treated cells, suggesting energy metabolism was increased. [ABSTRACT FROM AUTHOR]

Abstract: Differential immunoproteomics was applied to identify proteins secreted by Metarhizium anisopliae induced by the Rhipicephalus microplus cuticle. In addition, IgG anti-spore surface proteins were used for searching for proteins possibly involved in early stages of fungus versus tick infection. LC-MS/MS of differentially secreted proteins led to the identification of proteases (carboxypeptidase and Pr1A), chitinase, carboxylic acid transport and proline-rich protein. Differential immunoproteomics strategy facilitated the detection and the identification of new proteins related to M. anisopliae host–pathogen interaction and could be used in further works to identify novel proteins related to other microbial infection systems. [Copyright &y& Elsevier]

Although Metarhizium anisopliae is one of the most studied fungal biocontrol agents, its infection mechanism is far from being completely understood. Using multidimensional protein identification technology (MudPIT), we evaluated the differential secretome of M. anisopliae E6 induced by the host Rhipicephalus microplus cuticle. The proteomic result showed changes in the expression of 194 proteins after exposure to host cuticle, such as proteins involved in adhesion, penetration, stress and fungal defense. Further, we performed a comparative genomic distribution of differentially expressed proteins of the M. anisopliae secretome against another arthropod pathogen, using the Beauveria bassiana ARSEF2860 protein repertory. Among 47 analyzed protein families, thirty were overexpressed in the M. anisopliae E6 predicted genome compared to B. bassiana. An in vivo toxicity assay using a Galleria mellonella model confirmed that the M. anisopliae E6 secretome was more toxic in cattle tick infections compared to other secretomes, including B. bassiana with cattle ticks and M. anisopliae E6 with the insect Dysdereus peruvianus , which our proteomic results had also suggested. These results help explain molecular aspects associated with host infection specificity due to genetic differences and gene expression control at the protein level in arthropod-pathogenic fungi. [ABSTRACT FROM AUTHOR]

Secondary hypogonadism is a consequence of congenital or acquired diseases that affect the hypothalamus and/or pituitary gland, impairing secretion of gonadotrophin-releasing hormone (GnRH). Androgen deficiency resulting from reduced GnRH secretion is likely to have disrupting effects in epididymal epithelial cells, impairing the sperm maturation process. The aim of this study was to describe changes in the proteome of epididymal spermatozoa in a porcine model of secondary hypogonadism. Cauda epididymal spermatozoa were obtained from 10 boars previously immunised against GnRH (Vivax; Pfizer) and from 10 healthy boars. Protein extracts were analysed by multidimensional protein identification technology. In all, 1322 unique proteins were identified in the protein extracts of cauda epididymal spermatozoa, with significant changes in the abundance of key proteins involved in sperm metabolism (enolase, pyruvate dehydrogenase), acrosome reaction and capacitation (oxoprolinase, acrosomal protein SP-10, dihydrolipoyl dehydrogenase) and sperm–oocyte interactions (zona pellucida-binding protein, zonadhesin, sperm adhesion molecule 1). In addition, the abundance of mitochondrial proteins was severely affected, with significant changes in proteins of Complex I and II, as well as ATPase of the oxidative phosphorylation chain. The proteins identified in this study are potential sperm biomarkers of testicular and epididymal dysfunction related to disruption of the hypothalamus–pituitary–testis axis. Secondary hypogonadism is an important endocrine disorder that may decrease libido, impair erectile function, induce muscle weakness, increase adiposity, depress mood, decrease vitality and cause infertility. This study investigated the effects of secondary hypogonadism on the protein profile of epididymal spermatozoa in a swine model. Secondary hypogonadism induced significant changes in the proteome profile of epididymal spermatozoa, altering the abundance of key proteins involved in sperm metabolism, protection and fertilisation. [ABSTRACT FROM AUTHOR]

In the present study, we describe the proteome of porcine cauda epididymis fluid and spermatozoa by means of Multidimensional Protein Identification Technology (MudPIT). Ten sexually mature healthy boars were surgically castrated and epididymides were dissected to obtain the cauda epididymal content. Polled protein extracts of cauda epididymal fluid (CEF) and spermatozoa (CESperm) were loaded in an Agilent 1100 quaternary HPLC and peptides eluted from the microcapillary column were electro-sprayed directly into a LTQ Orbitrap XL mass spectrometer. Using bioinformatics, identified proteins were classified by their molecular functions, involvement in biological processes and participation in relevant metabolic pathways associated with spermatozoa physiology, fertility potential and protection. A total of 645 proteins were identified in the CEF, with epididymal-specific lipocalin-5, beta-hexosaminidase subunit beta precursor and phosphatidylethanolamine-binding protein 4 being the most abundant proteins found. A total of 2886 proteins were identified in the CESperm proteome with 81 proteins being considered more abundant (spectral counts > 100). CEF and CESperm data were compared and 345 proteins were present in both proteomes. Phosphatidylethanolamine-binding protein 4 precursor was the only protein found most abundant in both CEF and CESperm proteomes. Based on Gene Ontology analysis, we identified CEF and CESperm proteins associated with sperm protection against ROS and immune mediated response, glycosaminoglycan degradation, ubiquitin-proteasome system, metabolic process and maturation, modulation of acrosome reaction and ZP binding and oocyte penetration. These results provide a better comprehension about the molecular process and biological pathways involved in sperm epididymis maturation and establishment of the cauda epididymis sperm reservoir. [ABSTRACT FROM AUTHOR]