In the last years, tannase has been the subject of a lot of studies due to its commercial importance and complexity as catalytic molecule. Tannases are capable of hydrolyzing complex tannins, which represent the main chemical group of natural anti-microbials occurring in the plants. The general outline of this work includes information of the substrates, the enzyme, and the applications. This review considers in its introduction the concepts and history of tannase and explores scientific and technological aspects. The "advances" trace the route from the general, molecular, catalytic, and functional information obtained under close to optimal conditions for microbial production through purification, description of the enzyme properties, and the commercial applications to the "perspectives" including expression studies, regulation, and potential uses; aspects related to the progress in our understanding of tannin biodegradation are also included.

The extracellular proteome, or secretome, of phytopathogenic fungi is presumed to be a key element of their infection strategy. Especially interesting constituents of this set are those proteins secreted at the beginning of the infection, during the germination of conidia on the plant surfaces or wounds, since they may play essential roles in the establishment of a successful infection. We have germinated Botrytis cinerea conidia in conditions that resemble the plant environment, a synthetic medium enriched with low-molecular weight plant compounds, and we have collected the proteins secreted during the first 16 hours by a double precipitation protocol. 2D electrophoresis of the precipitated secretome showed a spot pattern similar for all conditions evaluated and for the control medium without plant extract. The proteins in 16 of these spots were identified by PMF and corresponded to 11 different polypeptides. Alternative determination of secretome composition by liquid chromatography-tandem mass spectrometry of tryptic fragments rendered a much larger number, 105 proteins, which included all previously identified by PMF. All proteins were functionally classified according to their putative function in the infection process. Key features of the early secretome include a large number of proteases, the abundance of proteins involved in the degradation of plant defensive barriers, and plenty of proteins with unknown function.

The main extracellular matrix binding component of the dystrophin-glycoprotein complex, ␣-dystroglycan (␣-DG), which was originally isolated from rabbit skeletal muscle, is an extensively O-glycosylated protein. Previous studies have shown ␣-DG to be modified by both O-GalNAc-and O-mannose-initiated glycan structures. O-Mannosylation, which accounts for up to 30% of the reported O-linked structures in certain tissues, has been rarely observed on mammalian proteins. Mutations in multiple genes encoding defined or putative glycosyltransferases involved in O-mannosylation are causal for various forms of congenital muscular dystrophy. Here, we explore the glycosylation of purified rabbit skeletal muscle ␣-DG in detail. Using tandem mass spectrometry approaches, we identify 4 O-mannose-initiated and 17 O-GalNAc-initiated structures on ␣-DG isolated from rabbit skeletal muscle. Additionally, we demonstrate the use of tandem mass spectrometry-based workflows to directly analyze glycopeptides generated from the purified protein. By combining glycomics and tandem mass spectrometry analysis of 91 glycopeptides from ␣-DG, we were able to assign 21 different residues as being modified by O-glycosylation with differing degrees of microheterogeneity; 9 sites of O-mannosylation and 14 sites of O-GalNAcylation were observed with only two sites definitively exhibiting occupancy by either type of glycan. The distribution of identified sites of O-mannosylation suggests a limited role for local primary sequence in dictating sites of attachment.Defects in protein glycosylation related to human disease were first reported in the 1980s, and since then, about 40 various types of congenital disorders of glycosylation have been reported (1). The term congenital disorders of glycosylation was first used to describe alterations of the N-glycosylation pathway and was later expanded to include the O-glycosylation pathways (1-3). The importance and complexity of O-linked glycosylation have only recently begun to be appreciated (1, 3, 4). In particular, mutations in genes encoding (putative) glycosyltransferases, which catalyze the addition and extension of O-linked mannose-initiated glycans, have garnered increased attention in the last decade given that they are causative for several forms of congenital muscular dystrophy (5, 6).The most common forms of O-glycosylation on secretory proteins are the mucin-like O-GalNAc structures that are initiated by polypeptide N-␣-acetylgalactosaminyltransferases in the endoplasmic reticulum-Golgi intermediate compartment and/or early cis-Golgi (7). Additionally, other O-linked structures are initiated with alternative monosaccharides, such as O-mannose, O-glucose, O-fucose, O-xylose, and O-GlcNAc onSer/Thr residues and the O-galactose modification of hydroxylysine residues in collagen domains (4). The diversity of O-mannosylated proteins in mammals, although quite abundant in some tissues (ϳ30% of O-glycans released from mouse brains (8)), has not been well characterized. The only clearly identified mamma...

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Botrytis cinerea is a pathogenic filamentous fungus which infects more than 200 plant species. The enzymes secreted by B. cinerea play an important role in the successful colonization of a host plant. Some of the secreted enzymes are involved in the degradation of pectin, a major component of the plant cell wall. A total of 126 proteins secreted by B. cinerea were identified by growing the fungus on highly or partially esterified pectin, or on sucrose in liquid culture. Sixty-seven common proteins were identified in each of the growth conditions, of which 50 proteins exhibited a Signal P motif. Thirteen B. cinerea proteins with functions related to pectin degradation were identified in both pectin growth conditions, while only four were identified in sucrose. Our results indicate it is unlikely that the activation of B. cinerea from the dormant state to active infection is solely dependent on changes in the degree of esterification of the pectin component of the plant cell wall. Further, these results suggest that future studies of the B. cinerea secretome in infections of ripe and unripe fruits will provide important information that will describe the mechanisms that the fungus employs to access nutrients and decompose tissues.