PgtE Enzyme of Salmonella enterica Shares the Similar Biological Roles to Plasminogen Activator (Pla) in Interacting With DEC-205 (CD205), and Enhancing Host Dissemination and Infectivity by Yersinia pestis

Yersinia pestis, the cause of plague, is a newly evolved Gram-negative bacterium. Through the acquisition of the plasminogen activator (Pla), Y. pestis gained the means to rapidly disseminate throughout its mammalian hosts. It was suggested that Y. pestis utilizes Pla to interact with the DEC-205 (CD205) receptor on antigen-presenting cells (APCs) to initiate host dissemination and infection. However, the evolutionary origin of Pla has not been fully elucidated. The PgtE enzyme of Salmonella enterica, involved in host dissemination, shows sequence similarity with the Y. pestis Pla. In this study, we demonstrated that both Escherichia coli K-12 and Y. pestis bacteria expressing the PgtE-protein were able to interact with primary alveolar macrophages and DEC-205-transfected CHO cells. The interaction between PgtE-expressing bacteria and DEC-205-expressing transfectants could be inhibited by the application of an anti-DEC-205 antibody. Moreover, PgtE-expressing Y. pestis partially re-gained the ability to promote host dissemination and infection. In conclusion, the DEC-205-PgtE interaction plays a role in promoting the dissemination and infection of Y. pestis, suggesting that Pla and the PgtE of S. enterica might share a common evolutionary origin.Peer reviewe

MAP Inference on Million Node Graphical Models: KL-divergence based Alternating Directions Method

Motivated by a problem in large scale climate data analysis, we consider the problem of maximum a posteriori (MAP) inference in graphical models with millions of nodes. While progress has been made in recent years, existing MAP inference algorithms are inherently sequential and hence do not scale well. In this paper, we present a parallel MAP inference algorithm called KL-ADM based on two ideas: tree-decomposition of a graph, and the alternating directions method (ADM). However, unlike standard ADM, we use an inexact ADM augmented with a Kullback-Leibler (KL) divergence based regularization. The unusual modification leads to an efficient iterative algorithm while avoiding double-loops. We rigorously prove global convergence of KL-ADM. We illustrate the effectiveness of KL-ADM through extensive experiments on large synthetic and real datasets. The application on real world precipitation data finds all major droughts in the last century

Effect of Compound Plant Essential Oil on Performance and Intestinal Microflora of Yellow-Feathered Broilers

【Objective】The trial explores the effect of compound plant essential oil from the nutmeg and basill on the performance and intestinal microflora of yellow-feathered broilers.【Method】3 942 1-day-old Jiangcun yellow broilers were divided into three treatments groups (low-dose compound essential oil group, high-dose compound essential oil group and blank control group). The experiment lasted for 60 days. At the age of 60 days, all broilers were weighed, and the number of survival chickens, the number of dead and unqualified chickens, feed consumption of each replicates were recorded, and the percentage of survival chickens, weight gain and feed-gain ratio were calculated. At the same time, 5 chickens were randomly selected from each group and killed with neck cut. The contents of jejunum and cecum were respectively extracted, and bacterial nucleic acid was extracted, the 16S rDNA V3-V4 variable region was high-throughput sequencing to analyze the intestinal microflora of jejunum and cecum of broilers.【Result】The feed-gain ratio of the high dose group and the low dose group was 2.40, which was significantly lower than that of the blank control group (2.71, P < 0.01), and the feed conversion rate was increased by 11.4%. The results of jejunum microflora analysis showed that Firmicutes were the dominant bacteria at phylum level followed by Actinobacteriota, and Lactobacillus was the dominant bacteria at genus level. The relative abundance of Verrucomicrobiota in jejunum in high-dose and low-dose groups was significantly lower than that in blank control group (P < 0.05). The relative abundance of Aeriscardovia, Bifidobacterium and Weissella in jejunum of compound essential oil low-dose group was significantly higher than that of blank control group (P < 0.05). The results of cecal microflora analysis showed that Firmicutes and Bacteroidetes were dominant bacteria at phylum level. The relative abundance of Clostridia_vadinBB60_group and Alistipes in high-dose and low-dose compound essential oil groups was significantly lower than that in blank control group (P < 0.05), and that of Clostridia_UCG-014 in high-dose compound essential oil group was significantly lower than that in blank control group (P < 0.05). The relative abundance of Bacteroides in high dose compound essential oil group was significantly higher than that in blank control group and low dose compound essential oil group (P < 0.05), and the relative abundance of Ruminococcus_torques_group in low dose compound essential oil group was significantly higher than that in blank control group (P < 0.05).【Conclusion】Feeding nutmeg and basil compound essential oil can promote the growth of beneficial bacteria in jejunum and cecum of yellow-feathered broilers, inhibit the proliferation of harmful bacteria, maintain the balance of bacteria, and promote intestinal health, and obviously improve the performance of yellow-feathered broilers

Nine New Phosphorene Polymorphs with Non-Honeycomb Structures: A Much Extended Family

We predict a new class of monolayer phosphorus allotropes, namely, ε-P, ζ-P, η-P, and θ-P. Distinctly different from the monolayer α-P (black) and previously predicted β-P (<i>Phys. Rev. Lett.</i> <b>2014</b>, <i>112</i>, 176802), γ-P, and δ-P (<i>Phys. Rev. Lett.</i> <b>2014</b>, <i>113</i>, 046804) with buckled honeycomb lattice, the new allotropes are composed of P₄ square or P₅ pentagon units that favor tricoordination for P atoms. The new four polymorphs, together with five additional hybrid polymorphs, greatly enrich the phosphorene structures, and their stabilities are confirmed by first-principles calculations. In particular, the θ-P is shown to be equally stable as the α-P (black) and more stable than all previously reported phosphorene polymorphs. Prediction of nonvolatile ferroelastic switching and structural transformation among different polymorphs under strains points out their potential applications via strain engineering