Hidden Genetic Variability within Electromorphs in Finite Populations

The amount of hidden genetic variability within electromorphs in finite populations is studied by using the infinite site model and stepwise mutation model simultaneously. A formula is developed for the bivariate probability generating function for the number of codon differences and the number of electromorph state differences between two randomly chosen cistrons. Using this formula, the distribution as well as the mean and variance of the number of codon differences between two identical or nonidentical electromorphs are studied. The distribution of the number of codon differences between two randomly chosen identical electromorphs is similar to the geometric distribution but more leptokurtic. Studies are also made on the number of codon differences between two electromorphs chosen at random one from each of two populations which have been separated for an arbitrary number of generations. It is shown that the amount of hidden genetic variability is very large if the product of effective population size and mutation rate is large.     

Design of an enzyme cocktail consisting of different fungal platforms for efficient hydrolysis of sugarcane bagasse: Optimization and synergism studies

Lignocellulosic materials represent a very important and promising source of renewable biomass. In order to turn them into fermentable sugars, synergism among the different enzymes that carry out bioconversion of these materials is one of the main factors that should be considered. Experimental mixture design was performed to optimize the proportion of enzymes produced by native strains of Trichoderma harzianum IOC 3844, Penicillium funiculosum ATCC 11797, and Aspergillus niger ATCC 1004, resulting in a proportion of 15, 50, and 35%, respectively. This mixture was able to hydrolyze 25 g/L of pretreated sugarcane bagasse with 91% of yield after 48 h of enzymatic reaction. Synergism along the hydrolysis process, besides the influence of lignin, hemicellulose, and solids loading, were also studied. Response surface methodology (RSM) based on Central Composite Rotatable Design was used to optimize solids and protein loadings to increase glucose release and enzymatic hydrolysis yield. The optimum solid and protein loadings established with RSM were 196 g/L and 24 mg/g cellulose, respectively, and under these conditions (94.1 ± 8) g/L of glucose were obtained, corresponding to a hydrolysis yield of 64%. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1222–1229, 2016     

Characterization of the cellulolytic secretome of Trichoderma harzianum during growth on sugarcane bagasse and analysis of the activity boosting effects of swollenin

This study demonstrates the production of an active enzyme cocktail produced by growing Trichoderma harzianum on sugarcane bagasse. The component enzymes were identified by LCMS‐MS. Glycosyl hydrolases were the most abundant class of proteins, representing 67% of total secreted protein. Other carbohydrate active enzymes involved in cell wall deconstruction included lytic polysaccharide mono‐oxygenases (AA9), carbohydrate‐binding modules, carbohydrate esterases and swollenin, all present at levels of 1%. In total, proteases and lipases represented 5 and 1% of the total secretome, respectively, with the rest of the secretome being made up of proteins of unknown or putative function. This enzyme cocktail was efficient in catalysing the hydrolysis of sugarcane bagasse cellulolignin to fermentable sugars for potential use in ethanol production. Apart from mapping the secretome of T. harzianum, which is a very important tool to understand the catalytic performance of enzyme cocktails, the gene coding for T. harzianum swollenin was expressed in Aspergillus niger. This novel aspect in this work, allowed increasing the swollenin concentration by 95 fold. This is the first report about the heterologous expression of swollenin from T. harzianum, and the findings are of interest in enriching enzyme cocktail with this important accessory protein which takes part in the cellulose amorphogenesis. Despite lacking detectable glycoside activity, the addition of swollenin of T. harzianum increased by two‐fold the hydrolysis efficiency of a commercial cellulase cocktail. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:327–336, 2016     

Diversity and evolution of T-cell receptor variable region genes in mammals and birds

 The receptor of a T lymphocyte (TCR) recognizes nonself antigens in the company of major histocompatibility complex (MHC) molecules presented to it by the antigen-presenting cell. The variable region of TCR is encoded by either a concatenation of variable region (TCR-V), diversity region (TCR-D), and joining region (TCR-J) genes, or a concatenation of TCR-V and TCR-J genes. The TCR-V genes exist as a multigene family in vertebrate species. Here we study the evolutionary relationships of TCR-V genes from humans, sheep, cattle, rabbits, mice, and chicken. These six species can be classified into two groups according to the frequency of γδ T-cells in their peripheral T-cell populations. The "γδ low" group of species includes humans and mice, in which γδ T-cells constitute very limited portion of the T-cell population. The "γδ high" group includes sheep, cattle, rabbits, and chicken, in which γδ T-cells comprise up to 60% of the T-cell population. Here, we compiled TCR-V sequences from the six species and conducted a phylogenetic analysis. We identified various TCR-V gene subgroups based on the analysis. We found that humans and mice have representatives from nearly all of the subgroups identified, while other species have lost subgroups to different extent. Therefore, the γδ low species have a high degree of diversity of TCR-V genes, while γδ high species all have limited diversity of TCR-V genes. This pattern is similar to that found for immunoglobulin variable region (IGV) genes. Received: 20 May 1999 / Revised: 13 July 1999     

A link between cytokinin and ASL9 (ASYMMETRIC LEAVES 2 LIKE 9) that belongs to the AS2/LOB (LATERAL ORGAN BOUNDARIES) family genes in Arabidopsis thaliana

In Arabidopsis thaliana, each member of a large family of AS2/LOB (ASYMMETRIC LEAVES 2/LATERAL ORGAN BOUNDARIES) genes encodes a plant specific protein. They are highly homologous to one other. A mutational lesion in the representative AS2 gene results in the development of anomalous asymmetric leaves, implying that these family members commonly play some roles in plant development. In this study, we found that ectopic overexpression of ASL9 (ASYMMETRIC LEAVES 2 LIKE 9) in transgenic plants displayed a markedly anomalous architecture during the development of adult plants. Then we found that among AS2/LOB family members, ASL9 is distinct from the others in that it is exclusively regulated by the plant hormone cytokinin in a manner dependent on His-Asp phosphorelay signal transduction. We further found that when supplied externally in a medium, cytokinin specifically affected the growth properties of ASL9-ox seedlings. Taken together, the results of this study suggest that the cytokinin-induced ASL9 gene is implicated in regulation of the development of Arabidopsis thaliana.     

Rhinocerebral Zygomycosis Due to a Lichtheimia ramosa Infection in a Calf: Neural Spread Through the Olfactory Nerves

Mycopathologia - Here, we report a case of rhinocerebral zygomycosis due to a Lichtheimia ramosa infection in a calf. A histopathological examination revealed that a fungus had invaded the brain...     

Generation and characterization of a monoclonal antibody, mH1, raised against mitotic HeLa cells

Hybridoma cell lines were prepared from spleen cells of mouse immunized with mitotic HeLa cells. A monoclonal antibody (mH1), which intensively reacted with cleavage furrows of dividing HeLa cells in immunofluorescence, was obtained. In interphase, this antibody diffusely stained whole HeLa cells. Immunoelectron microscopy showed that mH1 antigens were localized at microvillus projections at the surface of dividing HeLa cells, but definite localization of that antigen was not observed in interphasic cells. Immunoblot analysis showed that mH1 is reactive to 42-kDa and 130-kDa components. Further, the 42-kDa component was identified as a gamma-actin homolog by N-terminal amino acid sequence analysis.     

Two new species ofInocybe, sectionMarginatae (Agaricales, Cortinariaceae) from Japan

Two new species of the sectionMarginatae are described, namely,Inocybe populea sp. nov. andI. leptoclada sp. nov., from western Japan and eastern Japan, respectively.Inocybe leptoclada is assigned to sectionMarginatae, even though it lacks a marginate bulb.Inocybe populea is placed in the sectionMarginatae because of the presence of a marginate (often indistinct) bulbous base of stipe and the caulocystidia throughout. The discoveries ofI. leptoclada andI. populea provide further evidence that sectionMarginatae and sectionInocybe [=Cortinatae] are poorly defined.