Tim54p connects inner membrane assembly and proteolytic pathways in the mitochondrion

Tim54p, a component of the inner membrane TIM22 complex, does not directly mediate the import of inner membrane substrates but is required for assembly/stability of the 300-kD TIM22 complex. In addition, Deltatim54 yeast exhibit a petite-negative phenotype (also observed in yeast harboring mutations in the F1Fo ATPase, the ADP/ATP carrier, mitochondrial morphology components, or the i-AAA protease, Yme1p). Interestingly, other import mutants in our strain background are not petite-negative. We report that Tim54p is not involved in maintenance of mitochondrial DNA or mitochondrial morphology. Rather, Tim54p mediates assembly of an active Yme1p complex, after Yme1p is imported via the TIM23 pathway. Defective Yme1p assembly is likely the major contributing factor for the petite-negativity in strains lacking functional Tim54p. Thus, Tim54p has two independent functions: scaffolding/stability for the TIM22 membrane complex and assembly of Yme1p into a proteolytically active complex. As such, Tim54p links protein import, assembly, and turnover pathways in the mitochondrion.     

Molecular characterization of the complete mitochondrial genome sequence of Indian wild pig (Sus scrofa cristatus)

The Indian wild pig is a sub-species (Sus scrofa cristatus) which is different from the other pig breeds and is protected under Schedule-III of the Indian Wildlife (Protection) Act, 1972. In this study, complete mitogenome of two Indian wild pigs was sequenced and characterized by shotgun sequencing and de novo assembly, which revealed sequence size of 16,738 and 16,251?bp, respectively, (Accession no. MG725630 and MG725631). The mitogenome sequence in this study displayed 98% homology with previously reported mitogenome of pigs from different parts of the world. Mitogenome analysis by MITOS Web server revealed similarity of gene organization with the other vertebrates (13 protein-coding, 22 tRNAs, 2 rRNAs genes, and a control region). The mitogenomic sequences of Indian wild pig maintained a separate clade in the phylogenetic tree constructed by using 62 whole mitogenome sequences across the world. The phylogeny derived from mitogenomic sequences revealed distinct separate European–American and Asiatic pig clades. It was concluded that whole mitogenome sequencing using NGS without designing mitogenome-specific primer for amplification, is possible thereby reducing the cost and labor. This study is the first report of complete sequence of mitogenome of Indian wild pig.     

Phosphatidylserine Decarboxylase 1 Autocatalysis and Function Does Not Require a Mitochondrial-specific Factor

Phosphatidylethanolamine (PE) is a major cellular phospholipid that can be made by four separate pathways, one of which resides in the mitochondrion. The mitochondrial enzyme that generates PE is phosphatidylserine decarboxylase 1 (Psd1p). The pool of PE produced by Psd1p, which cannot be compensated for by the other cellular PE metabolic pathways, is important for numerous mitochondrial functions, including oxidative phosphorylation and mitochondrial dynamics and morphology, and is essential for murine development. To become catalytically active, Psd1p undergoes an autocatalytic processing step involving a conserved LGST motif that separates the enzyme into α and β subunits that remain non-covalently attached and are anchored to the inner membrane by virtue of the membrane-embedded β subunit. It was speculated that Psd1p autocatalysis requires a mitochondrial-specific factor and that for Psd1p to function in vivo, it had to be embedded with the correct topology in the mitochondrial inner membrane. However, the identity of the mitochondrial factor required for Psd1p autocatalysis has not been identified. With the goal of defining molecular requirements for Psd1p autocatalysis, we demonstrate that: 1) despite the conservation of the LGST motif from bacteria to humans, only the serine residue is absolutely required for Psd1p autocatalysis and function; 2) yeast Psd1p does not require its substrate phosphatidylserine for autocatalysis; and 3) contrary to a prior report, yeast Psd1p autocatalysis does not require mitochondrial-specific phospholipids, proteins, or co-factors, because Psd1p re-directed to the secretory pathway undergoes autocatalysis normally and is fully functional in vivo.     

Prevention and control of dengue and chikungunya in Colombia: A cost-effectiveness analysis

BackgroundChikungunya and dengue are emerging diseases that have caused large outbreaks in various regions of the world. Both are both spread by Aedes aegypti and Aedes albopictus mosquitos. We developed a dynamic transmission model of chikungunya and dengue, calibrated to data from Colombia (June 2014 –December 2017).Methodology/Principal findingsWe evaluated the health benefits and cost-effectiveness of residual insecticide treatment, long-lasting insecticide-treated nets, routine dengue vaccination for children aged 9, catchup vaccination for individuals aged 10–19 or 10–29, and portfolios of these interventions. Model calibration resulted in 300 realistic transmission parameters sets that produced close matches to disease-specific incidence and deaths. Insecticide was the preferred intervention and was cost-effective. Insecticide averted an estimated 95 chikungunya cases and 114 dengue cases per 100,000 people, 61 deaths, and 4,523 disability-adjusted life years (DALYs). In sensitivity analysis, strategies that included dengue vaccination were cost-effective only when the vaccine cost was 14% of the current price.Conclusions/SignificanceInsecticide to prevent chikungunya and dengue in Colombia could generate significant health benefits and be cost-effective. Because of limits on diagnostic accuracy and vaccine efficacy, the cost of dengue testing and vaccination must decrease dramatically for such vaccination to be cost-effective in Colombia. The vectors for chikungunya and dengue have recently spread to new regions, highlighting the importance of understanding the effectiveness and cost-effectiveness of policies aimed at preventing these diseases.     

Sequential search and the influence of male quality on female mating decisions

 The patterns of phenotypic association between mated males and females depend on the decision rules that individuals employ during search for a mate. We generalize the sequential search rule and examine how the shape of the function that relates a male character to the benefit of a mating decision influences the threshold value of the male trait that induces females to terminate search. If the fitness function is linear the optimal threshold value of a male character increases with the slope of the function. The phenotypic threshold criterion declines, all else being equal, if the fitness function is made more concave (or less convex) by an increase of the risk of the function. The expression of the trait in females has no effect on the optimal threshold value of a male character if the fitness function is linear and phenotypic values combine additively to influence the benefit of a mating decision; the phenotypic threshold criterion is ubiquitous among females. A convex fitness function induces females with high trait values to adopt a relatively high phenotypic threshold criterion, whereas a concave fitness function induces such females to adopt a low threshold value for the male trait. Thus, linear, convex and concave fitness functions effect random, assortative and disassortative combinations of phenotypes among mated individuals, respectively. Changes of female search behavior induced by changes of the distribution of a male character similarly depend on the shape of the fitness function. A variance-preserving increase of male trait values produces a relatively small increase of the threshold criterion for the male character if the fitness function is concave, relative to conditions in which the fitness function is either linear or convex. Our results suggest that a sequential search rule can in principle induce the kinds of mating patterns observed in nature and that the phenotypic association between mated individuals is likely to depend on how a male character translates into fitness, the distribution of the trait among males and attributes of searching females. Received: 20 September 1997 / Revised version: 13 August 1998     

Technoeconomic evaluation of bio-based styrene production by engineered Escherichia coli

Styrene is an important commodity chemical used in polymers and resins, and is typically produced from the petrochemical feedstocks benzene and ethylene. Styrene has recently been produced biosynthetically for the first time using engineered Escherichia coli, and this bio-based route may represent a lower energy and renewable alternative to petroleum-derived styrene. However, the economics of such an approach has not yet been investigated. Using an early-stage technoeconomic evaluation tool, a preliminary economic analysis of bio-based styrene from C₆-sugar feedstock has been conducted. Owing to styrene’s limited water solubility, it was assumed that the resulting fermentation broth would spontaneously form two immiscible liquid phases that could subsequently be decanted. Assuming current C₆ sugar prices and industrially achievable biokinetic parameter values (e.g., product yield, specific growth rate), commercial-scale bio-based styrene has a minimum estimated selling price (MESP) of 1.90 USD kg^?1 which is in the range of current styrene prices. A Monte Carlo analysis revealed a potentially large (0.45 USD kg^?1) standard deviation in the MESP, while a sensitivity analysis showed feedstock price and overall yield as primary drivers of MESP.     

A Distinct Strain of Cowpea mild mottle virus Infecting Soybean in India

Soybean crops showing systemic mottling, mosaic and leaf deformation were observed at high disease incidences (25.1–71.0%) in the kharif season of 2011 and 2012 in the experimental farm of the Indian Agricultural Research Institute (IARI), New Delhi. Symptomatic soybean leaves contained flexuous particles (650 × 12 nm), suggesting an infection by a Carlavirus. The causal virus was characterized as a strain of Cowpea mild mottle virus (CPMMV) on the basis of mechanical inoculation, whitefly transmission, seed transmission and sequencing of the viral genome. This is the first report of natural infection by a distinct strain of CPMMV in soybean in India.     

Jealousy evocation, partner reassurance, and relationship stability: An exploration of the potential benefits of jealousy

Three studies examined possible effects of jealousy evocation and jealous expression in romantic relationships. In Study 1, we used an indirect method to examine subjects' motivations for evoking jealousy in their romantic partners. Students' attributions for ambiguous interactions suggest that jealousy evocation is goal specific and that it is primarily used for mate retention. A majority of Study 1 participants also reported that they had previously attempted to evoke jealousy in a romantic partner to accomplish relationship goals. In Study 2, we examined the expected effect of jealousy evocation, from the perspective of the jealous partner. Here, results suggest that jealousy evocation is unlikely to produce immediate relationship benefits; in fact, it seems more likely to provoke fighting between romantic partners. Finally, in Study 3, we examined the longitudinal association of jealousy with relationship stability. Although there was a positive lagged correlation between participants' partners' jealousy and relationship stability, this association was not significant when participants' prior relationship commitment was controlled. This suggests that while jealousy itself is not causally related to relationship stability, a person's reactions to their jealous partner may be.     

Diversity and characterization of antagonistic bacteria from tropical estuarine habitats of Cochin, India for fish health management

Mortalities due to pathogenic bacteria are a major problem in aquaculture, especially in larval rearing systems. Use of antibiotics to overcome this problem is not an option any more due to the increasing antibiotic resistance among pathogens. The present study aims to understand the diversity of bacteria with antagonistic properties in the tropical estuarine habitats of Cochin, located along the southwest coast of India, and to use them as an alternative to antibiotics in aquaculture. Among the 4,870 isolates screened, approximately 1 % showed significant antibacterial activity against six common aquaculture pathogens belonging to the genera Aeromonas and Vibrio. The antagonistic bacteria were identified as Bacillus (81 %) and Pseudomonas (19 %) using biochemical and 16S rRNA gene sequence homology. The isolates showing stable and higher levels of antibacterial activity were subjected to enzymatic expression profile, antibiotic resistance pattern and abiotic stress tolerance assays. As a result, five Pseudomonas spp. and four Bacillus spp., were identified as promising antagonistic isolates that could be exploited as probionts or microbial products (MP's), to control bacterial diseases in aquaculture rearing systems.