Anti-Obesity Effect of Lactobacillus acidophilus DS0079 (YBS1) by Inhibition of Adipocyte Differentiation through Regulation of p38 MAPK/PPARγ Signaling.

Obesity is spawned by an inequality between the portion of energy consumed and the quantity of energy expended. Disease entities such as cardiovascular disease, arteriosclerosis, hypertension, and cancer, which are correlated with obesity, influence society and the economy. Suppression of adipogenesis, the process of white adipocyte generation, remains a promising approach for treating obesity. Oil Red O staining was used to differentiate 3T3-L1 cells for screening 20 distinct Lactobacillus species. Among these, Lactobacillus acidophilus DS0079, referred to as YBS1, was selected for further study. YBS1 therapy decreased 3T3-L1 cell development. Triglyceride accumulation and mRNA expression of the primary adipogenic marker, peroxisome proliferator-activated receptor gamma (PPARγ), including its downstream target genes, adipocyte fatty acid binding protein 4 and adiponectin, were almost eliminated. YBS1 inhibited adipocyte differentiation at the early stage (days 0-2), but no significant difference was noted between the mid-stage (days 2-4) and late-stage (days 4-6) development. YBS1 stimulated the activation of p38 mitogen-activated protein kinase (p38 MAPK) during the early stages of adipogenesis; however, this effect was eliminated by the SB203580 inhibitor. The data showed that YBS1 administration inhibited the initial development of adipocytes via stimulation of the p38 MAPK signaling pathway, which in turn controlled PPARγ expression. In summary, YBS1 has potential efficacy as an anti-obesity supplement and requires further exploration.

Veillonella faecalis sp. nov., a propionic acid-producing bacterium isolated from the faeces of an infant.

A strictly anaerobic, Gram-stain-negative, catalase-negative, cocci-shaped, and propionate-producing bacterial strain, named Ds1651T was isolated from the fecal sample collected from a South Korean infant. Through a comparison of 16S rRNA gene sequences, it was revealed that Ds1651T had the highest phylogenetic affinity with Veillonella nakazawae KCTC 25297 T (99.86%), followed by Veillonella infantium KCTC 25370 T (99.80%), and Veillonella dispar KCTC 25309 T (99.73%) in the family Veillonellaceae. Average nucleotide identity values between Ds1651T and three reference species were 95.48% for Veillonella nakazawae KCTC 25297 T, 94.46% for Veillonella infantium KCTC 25370 T, and 92.81% for Veillonella dispar KCTC 25309 T. The G + C content of Ds1651T was 38.58 mol%. Major fermentation end-products were acetic and propionic acids in Trypticase peptone glucose yeast extract broth with 1% (v/v) sodium lactate. The predominant cellular fatty acids that account for more than 10% were summed in Feature 8 (C17:1 ω8c and/or C17:2) and C13:0. Based on the findings from phylogenetic, genomic, phenotypic, and chemotaxonomic studies, we propose that the type strain Ds1651T (= KCTC 25477 T = GDMCC 1.3707 T) represents a novel bacterial species within the genus Veillonella, with the proposed name Veillonella faecalis sp. nov.

Disruptive Effects of Two Curcuminoids (Demethoxycurcumin and Bisdemethoxycurcumin) on the Larval Development of Drosophila melanogaster.

Juvenile hormones (JHs) play a central role in insect development, reproduction, and various physiological functions. Curcuminoids generally exhibit a wide range of biological activities, such as antioxidant, anti-inflammatory, antibacterial, and insecticidal, and they exhibit insect growth inhibitory effects. However, research on insecticidal properties of curcuminoids has been limited. Moreover, to the best of our knowledge, studies on JHs of insects and curcuminoids are lacking. Therefore, this study aimed to identify the substances that act as JH disruptors (JHDs) from edible plants. Demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC), two curcuminoids from the turmeric plant Curcuma longa L. inhibited the formation of a methoprene-tolerant (Met)-Taiman (Tai) heterodimer complex in Drosophila melanogaster, as shown through in vitro yeast two-hybrid assays. An artificial diet containing 1% (w/v) DMC or BDMC significantly reduced the number of D. melanogaster larvae in a concentration-dependent manner; larval development was disrupted, preventing the progression of larvae to pupal stages, resulting in an absence of adults. Building on the results obtained in this study on curcuminoids, researchers can use our study as a reference to develop eco-friendly pesticides.

Bifidobacterium bifidum DS0908 and Bifidobacterium longum DS0950 Culture-Supernatants Ameliorate Obesity-Related Characteristics in Mice with High-Fat Diet-Induced Obesity.

Probiotic supplements have promising therapeutic effects on chronic diseases. In this study, we demonstrated the anti-obesity effects of two potential probiotics, Bifidobacterium bifidum DS0908 (DS0908) and Bifidobacterium longum DS0950 (DS0950). Treatment with DS0908 and DS0950 postbiotics significantly induced the expression of the brown adipocyte-specific markers UCP1, PPARγ, PGC1α, PRDM16 and beige adipocyte-specific markers CD137, FGF21, P2RX5, and COX2 in C3H10T1/2 mesenchymal stem cells (MSCs). In mice with high-fat diet (HFD)-induced obesity, both potential probiotics and postbiotics noticeably reduced body weight and epididymal fat accumulation without affecting food intake. DS0908 and DS0950 also improved insulin sensitivity and glucose use in mice with HFD-induced obesity. In addition, DS0908 and DS0950 improved the plasma lipid profile, proved by reduced triglyceride, low-density lipoprotein, and cholesterol levels. Furthermore, DS0908 and DS0950 improved mitochondrial respiratory function, confirmed by the high expression of oxidative phosphorylation proteins, during thermogenesis induction in the visceral and epididymal fat in mice with HFD-induced obesity. Notably, the physiological and metabolic changes were more significant after treatment with potential probiotic culture-supernatants than those with the bacterial pellet. Finally, gene knockdown and co-treatment with inhibitor-mediated mechanistic analyses showed that both DS0908 and DS0950 exerted anti-obesity-related effects via the PKA/p38 MAPK signaling activation in C3H10T1/2 MSCs. Our observations suggest that DS0908 and DS0950 could potentially alleviate obesity as dietary supplements.

Systematic evaluation of genome-wide metabolic landscapes in lactic acid bacteria reveals diet- and strain-specific probiotic idiosyncrasies.

Lactic acid bacteria (LAB) are well known to elicit health benefits in humans, but their functional metabolic landscapes remain unexplored. Here, we analyze differences in growth, intestinal persistence, and postbiotic biosynthesis of six representative LAB and their interactions with 15 gut bacteria under 11 dietary regimes by combining multi-omics and in silico modeling. We confirmed predictions on short-term persistence of LAB and their interactions with commensals using cecal microbiome abundance and spent-medium experiments. Our analyses indicate that probiotic attributes are both diet and species specific and cannot be solely explained using genomics. For example, although both Lacticaseibacillus casei and Lactiplantibacillus plantarum encode similarly sized genomes with diverse capabilities, L. casei exhibits a more desirable phenotype. In addition, "high-fat/low-carb" diets more likely lead to detrimental outcomes for most LAB. Collectively, our results highlight that probiotics are not "one size fits all" health supplements and lay the foundation for personalized probiotic design.

Limosilactobacillus reuteri DS0384 promotes intestinal epithelial maturation via the postbiotic effect in human intestinal organoids and infant mice.

Little is known about the modulatory capacity of the microbiota in early intestinal development. We examined various intestinal models that respond to gut microbial metabolites based on human pluripotent stem cell-derived human intestinal organoids (hIOs): physiologically relevant in vitro fetal-like intestine, intestinal stem cell, and intestinal disease models. We found that a newly isolated Limosilactobacillus reuteri strain DS0384 accelerated maturation of the fetal intestine using 3D hIO with immature fetal characteristics. Comparative metabolomic profiling analysis revealed that the secreted metabolite N-carbamyl glutamic acid (NCG) is involved in the beneficial effect of DS0384 cell-free supernatants on the intestinal maturation of hIOs. Experiments in an intestinal stem cell spheroid model and hIO-based intestinal inflamed model revealed that the cell-free supernatant from DS0384 comprising NCG promoted intestinal stem cell proliferation and was important for intestinal protection against cytokine-induced intestinal epithelial injury. The probiotic properties of DS0384 were also evaluated, including acid and bile tolerance and ability to adhere to human intestinal cells. Seven-day oral administration of DS0384 and cell-free supernatant promoted the intestinal development of newborn mice. Moreover, NCG exerted a protective effect on experimental colitis in mice. These results suggest that DS0384 is a useful agent for probiotic applications and therapeutic treatment for disorders of early gut development and for preventing intestinal barrier dysfunction.

Inducible Expression of Several Drosophila melanogaster Genes Encoding Juvenile Hormone Binding Proteins by a Plant Diterpene Secondary Metabolite, Methyl Lucidone.

Juvenile hormones prevent molting and metamorphosis in the juvenile stages of insects. There are multiple genes encoding a conserved juvenile hormone binding protein (JHBP) domain in a single insect species. Although some JHBPs have been reported to serve as carriers to release hormones to target tissues, the molecular functions of the other members of the diverse JHBP family of proteins remain unclear. We characterized 16 JHBP genes with conserved JHBP domains in Drosophila melanogaster. Among them, seven JHBP genes were induced by feeding the flies with methyl lucidone, a plant diterpene secondary metabolite (PDSM). Induction was also observed upon feeding the juvenile hormone (JH) analog methoprene. Considering that methyl lucidone and methoprene perform opposite functions in JH-mediated regulation, specifically the heterodimeric binding between a JH receptor (JHR) and steroid receptor coactivator (SRC), the induction of these seven JHBP genes is independent of JH-mediated regulation by the JHR/SRC heterodimer. Tissue-specific gene expression profiling through the FlyAtlas 2 database indicated that some JHBP genes are mainly enriched in insect guts and rectal pads, indicating their possible role during food uptake. Hence, we propose that JHBPs are induced by PDSMs and respond to toxic plant molecules ingested during feeding.

Human gut-microbiome-derived propionate coordinates proteasomal degradation via HECTD2 upregulation to target EHMT2 in colorectal cancer.

The human microbiome plays an essential role in the human immune system, food digestion, and protection from harmful bacteria by colonizing the human intestine. Recently, although the human microbiome affects colorectal cancer (CRC) treatment, the mode of action between the microbiome and CRC remains unclear. This study showed that propionate suppressed CRC growth by promoting the proteasomal degradation of euchromatic histone-lysine N-methyltransferase 2 (EHMT2) through HECT domain E3 ubiquitin protein ligase 2 (HECTD2) upregulation. In addition, EHMT2 downregulation reduced the H3K9me2 level on the promoter region of tumor necrosis factor α-induced protein 1 (TNFAIP1) as a novel direct target of EHMT2. Subsequently, TNFAIP1 upregulation induced the apoptosis of CRC cells. Furthermore, using Bacteroides thetaiotaomicron culture medium, we confirmed EHMT2 downregulation via upregulation of HECTD2 and TNFAIP1 upregulation. Finally, we observed the synergistic effect of propionate and an EHMT2 inhibitor (BIX01294) in 3D spheroid culture models. Thus, we suggest the anticancer effects of propionate and EHMT2 as therapeutic targets for colon cancer treatment and may provide the possibility for the synergistic effects of an EHMT2 inhibitor and microbiome in CRC treatment.

Bifidobacterium longum subsp. infantis YB0411 Inhibits Adipogenesis in 3T3-L1 Pre-adipocytes and Reduces High-Fat-Diet-Induced Obesity in Mice.

Although the health benefits of probiotics have been widely known for decades, there has still been limited use of probiotic bacteria in anti-obesity therapy. Herein, we demonstrated the role of Bifidobacterium longum subsp. infantis YB0411 (YB, which was selected by an in vitro adipogenesis assay) in adipogenic differentiation in 3T3-L1 pre-adipocytes. We observed that YB-treatment effectively reduced triglyceride accumulation and the expression of CCAAT/enhancer-binding protein α, ß, and δ (C/EBPα, C/EBPß, and C/EBPδ), peroxisome proliferator-activated receptor γ (PPARγ), fatty acid-binding protein 4 (aP2), and acetyl-CoA carboxylase (ACC). YB-treatment also reduced the levels of core autophagic markers (p62 and LC3B) in 3T3-L1 pre-adipocytes. Small-interfering-RNA-mediated knockdown and competitive-chemical-inhibition assays showed that AMP-activated protein kinase (AMPK) commenced the anti-adipogenic effect of YB. In addition, YB supplement markedly reduced body weight and fat accretion in mice with high-fat-diet-induced obesity. Our findings suggest that YB may be used as a potential probiotic candidate to ameliorate obesity.

Lactobacillus reuteri AN417 cell-free culture supernatant as a novel antibacterial agent targeting oral pathogenic bacteria.

Lactobacillus reuteri AN417 is a newly characterized probiotic strain. The activity of AN417 against oral pathogenic bacteria is unknown. We investigated the antibacterial activity of cell-free L. reuteri AN417 culture supernatant (LRS) against three oral pathogens: Porphyromonas gingivalis, Fusobacterium nucleatum, and Streptococcus mutans. P. gingivalis and F. nucleatum have been implicated in periodontal disease, whereas S. mutans causes dental caries. Exposing these oral pathogenic bacteria to LRS significantly reduced their growth rates, intracellular ATP levels, cell viability, and time-to-kill. The minimal inhibitory volume of LRS was 10% (v/v) against P. gingivalis, 20% (v/v) for F. nucleatum, and 30% (v/v) for S. mutans. LRS significantly reduced the integrity of biofilms and significantly suppressed the expression of various genes involved in P. gingivalis biofilm formation. The L. reuteri AN417 genome lacked genes encoding reuterin, reuteran, and reutericyclin, which are major antibacterial compounds produced in L. reuteri strains. LRS treated with lipase and α-amylase displayed decreased antibacterial activity against oral pathogens. These data suggest that the antibacterial substances in LRS are carbohydrates and/or fatty acid metabolites. Our results demonstrate that LRS has antimicrobial activity against dental pathogenic bacteria, highlighting its potential utility for the prevention and treatment of P. gingivalis periodontal disease.

The complete mitochondrial genome of Alphitobius diaperinus Panzer, 1797 (Coleoptera: Tenebrionidae).

Alphitobius diaperinus Panzer, 1797 is a major pest in poultry production and easily observed in poultry litter. We have determined mitochondrial genome of A. diaperinus collected in Chungcheongbuk-do, Republic of Korea. The circular mitogenome of A. diaperinus is 15,511 bp long which is longer than that of Z. atratus but shorter than that of T. obscurus. It includes 13 protein-coding genes, two ribosomal RNA genes, and 22 transfer RNAs. The base composition was AT-biased (72.4%). Phylogenetic tree displays that tribe Alphitobiini is clustered with tribes Helopini and Diaperini with enough supportive values of three phylogenetic trees.

Maturation of human intestinal organoids in vitro facilitates colonization by commensal lactobacilli by reinforcing the mucus layer.

Lactobacilli, which are probiotic commensal bacteria that mainly reside in the human small intestine, have attracted attention for their ability to exert health-promoting effects and beneficially modulate host immunity. However, host epithelial-commensal bacterial interactions are still largely unexplored because of limited access to human small intestinal tissues. Recently, we described an in vitro maturation technique for generating adult-like, mature human intestinal organoids (hIOs) from human pluripotent stem cells (hPSCs) that closely resemble the in vivo tissue structure and cellular diversity. Here, we established an in vitro human model to study the response to colonization by commensal bacteria using luminal microinjection into mature hIOs, allowing for the direct examination of epithelial-bacterial interactions. Lactobacillus reuteri and Lactobacillus plantarum were more likely to survive and colonize when microinjected into the lumen of mature hIOs than when injected into immature hIOs, as determined by scanning electron microscopy, colony formation assay, immunofluorescence, and real-time imaging with L plantarum expressing red fluorescent protein. The improved mature hIO-based host epithelium system resulted from enhanced intestinal epithelial integrity via upregulation of mucus secretion and tight junction proteins. Our study indicates that mature hIOs are a physiologically relevant in vitro model system for studying commensal microorganisms.

Lactococcus kimchii sp. nov., a new lactic acid bacterium isolated from kimchi.

A coccus strain designated S-13T was isolated from commercial baechu-kimchi in Korea. Comparison of the 16S rRNA gene sequence indicated that strain S-13T had the highest similarity to Lactococcus taiwanensis 0905C15T (97.9 %), Lactococcus lactis subsp. tructae L105T (97.6 %), Lactococcus lactis subsp. cremoris NCDO 607T (97.5 %), Lactococcus lactis subsp. hordniae NBRC 100931T (97.2 %), and Lactococcus lactis subsp. lactis JCM 5805T (97.2 %). The detailed phylogenetic analyses based on the 16S rRNA, rpoB and recA genes indicated that S-13T was separated from the other species and subspecies in the genus Lactococcus. The DNA-DNA relatedness between S-13T and closely related type strains, such as L. taiwanensis 0905C15T, L. lactis subsp. tructae L105T, L. lactis subsp. cremoris NCDO 607T, L. lactis subsp. hordniae NBRC 100931T, and L. lactis subsp. lactis JCM 5805T was 25.6, 20.4, 25.1, 20.2 and 21.7 %, respectively. The major fatty acids were C16 : 0, cyclo-C19 : 0ω8c and C 14 : 0. The DNA G+C content of S-13T was 39.4 mol%. From the results of the phenotypic characteristics and chemotaxonomic analysis, it was concluded that strain S-13T represents a novel species in the genus Lactococcus for which the name Lactococcus kimchii sp. nov. (=KCTC 21096T=NBRC 113348T) is proposed.

Thermomonas aquatica sp. nov., isolated from an industrial wastewater treatment plant.

A white-coloured, Gram-stain-negative, aerobic, rod-shaped bacterium (designated strain SY21T) was isolated from waste-activated sludge. Optimal growth occurred at 28 °C and pH 7.0. Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain SY21T exhibited 16S rRNA gene sequence similarities of 95.5-98.0 % to Thermomonas species and clustered with the type species of the genus Thermomonas. In strain SY21T, the predominant respiratory quinone was ubiquinone Q-8, and the cellular fatty acids consisted mainly of iso-C15 : 0, C16 : 0, iso-C11 : 0 3-OH, summed feature 3 and summed feature 9. The major polar lipids were phosphatidylcholine, phosphatidylglycerol and phosphatidylethanolamine. The genomic DNA G+C content was determined to be 67.9 mol% and the DNA-DNA relatedness between strain SY21T and the closest phylogenetically related strain, Thermomonas carbonis KCTC 42013T, was 35.0±0.1 %. Based on the distinct phenotypic, chemotaxonomic and phylogenetic properties, strain SY21T represents a novel species of the genus Thermomonas, for which the name Thermomonas aquatica sp. nov. is proposed. The type strain is SY21T (=KCTC 62191T=NBRC 113114T).

Intestinibaculum porci gen. nov., sp. nov., a new member of the family Erysipelotrichaceae isolated from the small intestine of a swine.

A strictly anaerobic, Gram-stain-positive, catalase-negative, non-motile, rod-shaped bacterium, designated SG0102T, was isolated from the small intestine of a swine. Optimal growth occurred at 37°C and pH 7.0. Furthermore, growth was observed in the presence of up to 3% (w/v) NaCl but not at salinity levels higher than 4%. The comparative analysis of 16S rRNA gene sequences showed that strain SG0102T was most closely related to Kandleria vitulina DSM 20405T (93.3%), followed by Catenibacterium mitsuokai KCTC 5053T (91.1%), Sharpea azabuensis KCTC 15217T (91.0%), and Eggerthia catenaformis DSM 5348T (89.6%). The average nucleotide identity values between strain SG0102T and related species, K. vitulina DSM 20405T, C. mitsuokai KCTC 5053T, S. azabuensis KCTC 15217T, and E. catenaformis DSM 5348T, were 71.0, 69.3, 70.0, and 69.2%, respectively. The phylogenetic analysis based on 16S rRNA gene sequence revealed that strain SG0102T belonged to the family Erysipelotrichaceae in the class Erysipelotrichia. The DNA G + C content of the strain SG0102T was 39.5 mol%. The major cellular fatty acids (> 10%) of strain SG0102T were C16:0, C16:0 dimethyl acetal, and C18:2ω9/12c. The cell wall peptidoglycan of strain SG0102T contained the meso-diaminopimelic acid. The strain SG0102T produced lactic acid as a major end product of fermentation. These distinct phenotypic and phylogenetic properties suggest that strain SG0102T represents a novel species in a novel genus of the family Erysipelotrichaceae, for which the name Intestinibaculum porci gen. nov. sp. nov. is proposed. The type strain is SG0102T (= KCTC 15725T = NBRC 113396T).

Correction: Bacterial diversity of bat guano from Cabalyorisa Cave, Mabini, Pangasinan, Philippines: A first report on the metagenome of Philippine bat guano.

[This corrects the article DOI: 10.1371/journal.pone.0200095.].

Lactobacillus porci sp. nov., isolated from small intestine of a swine.

A facultatively anaerobic, Gram-stain-positive, catalase-negative, rod-shaped lactic acid bacterium, designated SG816T, was isolated from small intestine of a swine. Optimal growth occurred at 37 °C and pH 7.0. Furthermore, growth occurred in NaCl up to 0.5 % (w/v) but not at levels of salinity higher than 1 %. Comparative 16S rRNA gene sequencing and the matrix-associated laser desorption/ionization-time-of-flight mass spectometry profiling showed that strain SG816T was closely related to Lactobacillus delbrueckiisubsp. bulgaricus KCTC 3635T (95.9 %) and Lactobacillus delbrueckiisubsp. indicus JCM 15610T (95.9 %), followed by other Lactobacillus delbrueckii subspecies (95.9-95.7 %) and Lactobacillus equicursoris DSM 19284T (95.6 %). A comparison of two housekeeping genes, RNA polymerase alpha subunit (rpoA) and phenylalanyl-tRNA synthase alpha subunit (pheS), revealed that strain SG816T formed a separate branch within the clade of the genus Lactobacillus. The DNA G+C content level of the strain SG816T was 51.5 mol%. The strain was homofermentative and produced d-lactic acid from glucose fermentation. The major cellular fatty acids (>10 %) of the isolate were C18 : 1ω9c and C16 : 0. The peptidoglycan type was A4α l-Lys-d-Asp. On the basis of distinct phenotypic and phylogenetic properties, strain SG816T represents a novel species of the genus Lactobacillus, for which the name Lactobacillus porci sp. nov. is proposed. The type strain is SG816T (=KCTC 21090T=NBRC 112917T).

A plant diterpene counteracts juvenile hormone-mediated gene regulation during Drosophila melanogaster larval development.

Many plant species possess compounds with juvenile hormone disruptor (JHD) activity. In some plant species, such activity has been attributed to diterpene secondary metabolites. Plant JHD diterpenes disrupt insect development by interfering with the juvenile hormone (JH)-mediated formation of JH receptor complexes. Here, we demonstrate that a plant extract and a diterpene from Lindera erythrocarpa (methyl lucidone) interfere with the formation of both methoprene-tolerant (Met)/Taiman and Germ cell-expressed (GCE)/Taiman heterodimer complexes in yeast two-hybrid assays in vitro. In addition to the in vitro JHD activity, the diterpene and the plant extract from L. erythrocarpa also disrupt the development of larvae and pupae in Drosophila melanogaster. Comparing the transcriptomes of juvenile hormone analog (JHA, methoprene)- and JHD (methyl lucidone)-fed wandering third-instar larvae revealed a large number of genes that were coregulated by JHA and JHD. Moreover, most (83%) of the genes that were repressed by methyl lucidone were significantly activated by methoprene, indicating that JHDs and JHAs have opposing effects on the transcriptional regulation of many JH-dependent genes. Gene ontology analysis also suggested that some of the genes activated-by-JHA/repressed-by-JHD play roles in spermatogenesis. Affymetrix microarray-based analysis indicated that the expression of genes activated-by-JHA/repressed-by-JHD was testis-specific. Together, these results suggest that JH is involved in testis-specific gene expression and that plant JHD diterpenes function as JH antagonists in such JHA-mediated gene regulation.

Bacterial diversity of bat guano from Cabalyorisa Cave, Mabini, Pangasinan, Philippines: A first report on the metagenome of Philippine bat guano.

Bats are highly diverse and ecologically valuable mammals. They serve as host to bacteria, viruses and fungi that are either beneficial or harmful to its colony as well as to other groups of cave organisms. The bacterial diversity of two bat guano samples, C1 and C2, from Cabalyorisa Cave, Mabini, Pangasinan, Philippines were investigated using 16S rRNA gene amplicon sequencing. V3-V4 hypervariable regions were amplified and then sequenced using Illumina MiSeq 250 PE system. Reads were processed using Mothur and QIIME pipelines and assigned 12,345 OTUs for C1 and 5,408 OTUs for C2. The most dominant OTUs in C1 belong to the Proteobacteria (61.7%), Actinobacteria (19.4%), Bacteroidetes (4.2%), Firmicutes (2.7%), Chloroflexi (2.5%), candidate phylum TM7 (2.3%) and Planctomycetes (1.9%) while Proteobacteria (61.7%) and Actinobacteria (34.9%) dominated C2. Large proportion of sequence reads mainly associated with unclassified bacteria indicated possible occurrence of novel bacteria in both samples. XRF spectrophotometric analyses of C1 and C2 guano revealed significant differences in the composition of both major and trace elements. C1 guano recorded high levels of Si, Fe, Mg, Al, Mn, Ti and Cu while C2 samples registered high concentrations of Ca, P, S, Zn and Cr. Community structure of the samples were compared with other published community profiling studies from Finland (SRR868695), Meghalaya, Northeast India (SRR1793374) and Maharashtra State, India (CGS). Core microbiome among samples were determined for comparison. Variations were observed among previously studied guano samples and the Cabalyorisa Cave samples were attributed to either bat sources or age of the guano. This is the first study on bacterial diversity of guano in the Philippines through high-throughput sequencing.

Species-Specific Interactions between Plant Metabolites and Insect Juvenile Hormone Receptors.

Because juvenile hormone (JH) controls insect development and its analogs are used as insecticides, juvenile hormone disruptors (JHDs) represent potential sources from which novel pesticides can be developed. Many plant species harbor JHD activity, which has previously been attributed plant secondary metabolites (i.e., diterpenes) that disrupt insect development by interfering with the JH-mediated heterodimer formation of insect juvenile receptor complexes. The results of the present study indicate that plant JHD activity is also concentrated in certain plant groups and families and that plant metabolites have insect group-specific activity. These findings suggest that reciprocal diversification has occurred between plants and insects through the evolution of the plant metabolites and JH receptors, respectively, and that plant metabolites could be developed into insect group-specific pesticides with limited effects on non-target species.