To identify genes that regulate the dynamics of lipid droplet (LD) size, we have used the genetically tractable model organism Caenorhabditis elegans, whose wild-type LD population displays a steady state of size with an upper limit of 3 μm in diameter. From a saturated forward genetic screen of 6.7 × 105 mutagenized haploid genomes, we isolated 118 mutants with supersized intestinal LDs often reaching 10 μm. These mutants define nine novel complementation groups, in addition to four known genes (maoc-1, dhs-28, daf-22, and prx-10). The nine groups are named drop (lipid droplet abnormal) and categorized into four classes. Class I mutants drop-5 and drop-9, similar to prx-10, are up-regulated in ACS-22-DGAT-2-dependent LD growth, resistant to LD hydrolysis, and defective in peroxisome import. Class II mutants drop-2, drop-3, drop-6, and drop-7 are up-regulated in LD growth, are resistant to LD hydrolysis, but are not defective in peroxisome import. Class III mutants drop-1 and drop-8 are neither up-regulated in LD growth nor resistant to LD hydrolysis, but seemingly up-regulated in LD fusion. Class IV mutant drop-4 is cloned as sams-1 and, different to the other three classes, is ACS-22-independent and hydrolysis-resistant. These four classes of supersized LD mutants should be valuable for mechanistic studies of LD cellular processes including growth, hydrolysis, and fusion.

National Molecular Tracing Network for Foodborne Disease Surveillance (TraNet) was launched in 2013, which is the only real-time whole-genome sequencing (WGS)-based subtyping network in China for effective foodborne disease surveillance. TraNet covers three levels of public health laboratories, national, provincial, and municipal. The TraNet national databases have a total of more than 54,000 entries representing seven common foodborne bacteria from humans, food, and environments. Raw sequence data are uploaded to TraNet by Data Delivery Center. Assembled sequence data, pulsed-field gel electrophoresis (PFGE) profiles, antibiotic resistance patterns, and epidemiological data are submitted to national pathogen-specific databases managed by China National Center for Food Safety Risk Assessment. PFGE patterns and WGS-based subtyping are compared for rapid differentiation of clusters of geographically diverse foodborne infections. WGS-based TraNet has played significant roles in improving foodborne disease surveillance in China for rapid outbreak investigation, source tracking, and cluster analysis of particular pathogens across the country.

Nuclear receptors play important roles in regulating fat metabolism and energy production in humans. The regulatory functions and endogenous ligands of many nuclear receptors are still unidentified, however. Here, we report that CYP-37A1 (ortholog of human cytochrome P450 CYP4V2), EMB-8 (ortholog of human P450 oxidoreductase POR), and DAF-12 (homolog of human nuclear receptors VDR/LXR) constitute a hormone synthesis and nuclear receptor pathway in This pathway specifically regulates the thermosensitive fusion of fat-storing lipid droplets. CYP-37A1, together with EMB-8, synthesizes a lipophilic hormone not identical to Δ7-dafachronic acid, which represses the fusion-promoting function of DAF-12. CYP-37A1 also negatively regulates thermotolerance and lifespan at high temperature in a DAF-12-dependent manner. Human CYP4V2 can substitute for CYP-37A1 in This finding suggests the existence of a conserved CYP4V2-POR-nuclear receptor pathway that functions in converting multilocular lipid droplets to unilocular ones in human cells; misregulation of this pathway may lead to pathogenic fat storage.

What is already known on this topic? Streptococcus suis ( S. suis ) is a zoonotic pathogen causing disease in humans and animals, and the emergence of its increased resistance to antimicrobial agents has become a significant challenge in many countries. What is added by this report? Using whole genome sequencing data to accurately predict antimicrobial resistance determinants, it was found that the prevalence of antimicrobial resistance genes was higher in the pig isolates of S. suis than in the human isolates and that the prevalence of these genes varied with serotype. What are the implications for public health practice? The data regarding S. suis antimicrobial resistance will help guide rational drug use in the clinic to better protect the health of humans and animals.

The proportion of campylobacteriosis caused by C. coli is increasing rapidly in China. Coincidentally, the dominant species of Campylobacter occurring in poultry products has shifted from C. jejuni to C. coli .