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Insect-induced galls are an atypical growth and differentiation form of plant tissue. The objective of this research was to study the expression of photosynthesis-associated proteins in Cecidomyiidae galls derived from the leaves of Litsea acuminata using a Western blot analysis of antibodies against light-harvesting complex (LHC) proteins isolated from non-galled and galled leaves and gall tissues. These LHC proteins involved in RC-1a, RC-1b, LHCb4, LHCb5, CP47, and CP-1a showed different responses in galls and leaves and exhibited a remarkable potential modulation role in regulating gall development. All photosynthetic proteins were repressed in gall tissues, indicating that light reaction functioning was significantly repressed. Compared to non-galled and galled leaves, galls demonstrated significantly lower chlorophyll (Chl) content and photosystem II maximum quantum efficiency (Fv/Fm) values, suggesting that insect infestations reduced photosynthetic efficiency. In addition, there were significant and positive correlations between LHCb5, CP-1a, and CP47 vs. Fv/Fm values and Chl content in galls and leaves, indicating that gall infections induced physiological changes, and therefore, that the Fv/Fm value could be utilized as a tool to easily and quickly study the eco-physiology of galls.

The objective of this research was to study altered distributions of chloroplasts in cecidomyiid galls derived from the leaves of Machilus thunbergii Sieb. & Zucc. and Litsea acuminata (Blume) Kurata using confocal laser-scanning microscopy and transmittance spectra. Chloroplasts in all gall tissues gradually decreased in the direction from the exterior toward the inside larval chamber based on Integrated Optical Density (IOD) and absorptivity indices, and chloroplast distributions in various gall tissues were species-specific. Different species of herbivorous insect dramatically altered chloroplasts in their host leaves. The spectral index was significantly and positively correlated with the IOD, and therefore, the transmittance spectra could be utilized as a tool to easily and quickly study the ecophysiology of galls.

Terpios hoshinota is an aggressive, space-competing sponge that kills various stony corals. Outbreaks of this species have led to intense damage to coral reefs in many locations. Here, the first large-scale 16S rRNA gene survey across three oceans revealed that bacteria related to the taxa Prochloron, Endozoicomonas, SAR116, Ruegeria, and unclassified Proteobacteria were prevalent in T. hoshinota. A Prochloron-related bacterium was the most dominant and prevalent cyanobacterium in T. hoshinota. The complete genome of this uncultivated cyanobacterium and pigment analysis demonstrated that it has phycobiliproteins and lacks chlorophyll b, which is inconsistent with the definition of Prochloron. Furthermore, the cyanobacterium was phylogenetically distinct from Prochloron, strongly suggesting that it should be a sister taxon to Prochloron. Therefore, we proposed this symbiotic cyanobacterium as a novel species under the new genus Candidatus Paraprochloron terpiosi. Comparative genomic analyses revealed that 'Paraprochloron' and Prochloron exhibit distinct genomic features and DNA replication machinery. We also characterized the metabolic potentials of 'Paraprochloron terpiosi' in carbon and nitrogen cycling and propose a model for interactions between it and T. hoshinota. This study builds a foundation for the study of the T. hoshinota microbiome and paves the way for better understanding of ecosystems involving this coral-killing sponge.

Extreme temperatures have become a threat to crop yields. To maintain plant growth and yield, chlorophyll (Chl) biosynthesis plays a crucial role in adaptation to temperature stress. This study investigated the influence of temperature on the biosynthesis and characteristics of pigments (Chl a, Chl b, and carotenoids) in the leaves of Chl b-lacking mutant rice (Chlorina 1, ch1) and wild-type rice (Norin No.8, wt). The ch1 showed thinner stacked grana caused by a decrease in thylakoid membranes per granum at 15 °C, whereas the destacked grana were observed at 35 °C after 12 h incubation. However, the grana are stacked normally, along with the absence of Chl b, and a significantly decreased amount of Chl a in both wt and ch1 were observed after heat stress exposure, demonstrating that light-harvesting complex II proteins are involved in grana stacking. Ch1 was sensitive to 15 °C during the first 4 h of incubation but it subsequently adapted to the cold environment. In addition, there were no significant differences in the photosynthesis between wt and ch1 after 12 h incubation at 35 °C. Differentially expressed gene (DEGs) analysis revealed that GluRS expression decreased, which resulted in a decline in Chl biosynthesis in wt and ch1 at 35 °C. At 8 h and 12 h, there were no significant differences in the expression of DEGs involved in Chl biosynthesis and degradation between wt and ch1 at 15 °C. ALAD expression in wt and ch1 at 15 °C decreased until it was undetectable. These findings suggested that ch1 may adapt to temperatures ranging from 15 °C to 35 °C.

Photosynthesis is an essential biological process and a key approach for raising crop yield. However, photosynthesis in rice is not fully investigated. This study reported the photosynthetic properties and transcriptomic profiles of chlorophyll (Chl) b-deficient mutant (ch11) and wild-type rice (Oryza sativa L.). Chl b-deficient rice revealed irregular chloroplast development (indistinct membranes, loss of starch granules, thinner grana, and numerous plastoglobuli). Next-generation sequencing approach application revealed that the differential expressed genes were related to photosynthesis machinery, Chl-biosynthesis, and degradation pathway in ch11. Two genes encoding PsbR (PSII core protein), FtsZ1, and PetH genes, were found to be down-regulated. The expression of the FtsZ1 and PetH genes resulted in disrupted chloroplast cell division and electron flow, respectively, consequently reducing Chl accumulation and the photosynthetic capacity of Chl b-deficient rice. Furthermore, this study found the up-regulated expression of the GluRS gene, whereas the POR gene was down-regulated in the Chl biosynthesis and degradation pathways. The results obtained from RT-qPCR analyses were generally consistent with those of transcription analysis, with the exception of the finding that MgCH genes were up-regulated which enhance the important intermediate products in the Mg branch of Chl biosynthesis. These results indicate a reduction in the accumulation of both Chl a and Chl b. This study suggested that a decline in Chl accumulation is caused by irregular chloroplast formation and down-regulation of POR genes, and Chl b might be degraded via the pheophorbide b pathway, which requires further elucidation.

Background: Chlorophyllases (Chlases) are housekeeping proteins in plant cells. The dephytylating enzymes can catalyze chlorophyll (Chl) to form chlorophyllide, but the distribution of Chlases in plant cells is still an interesting debate. In this study, antibody of PmCLH2 was made and used by immunogold-labelling technique to detect the location of Chlase of Pachira macrocarpa (Pm) leaves at four developmental stages, including young, mature, yellowing, and senesced stages. Results: The transmission electron microscopy results show that Chlases were comprehensively found in portions of chloroplast, such as the inner membrane of the envelope, grana, and the thylakoid membrane of the chloroplast, cytosol, and vacuoles at young, mature, and yellowing stages of Pm leaves, but not in the cell wall, plasma membrane, mitochondria, and nucleus. Conclusions: PmChlases were mainly detected in vacuoles at the senescent stage, but a few were found in the chloroplasts. A pathway is proposed to explain the birth and death of Chl, Chlase, and chloroplasts in higher plants.

Terpios hoshinota is a ferocious, space-competing sponge that kills a variety of stony corals by overgrowth. Outbreaks of this species have led to intense coral reef damage and declines in living corals on the square kilometer scale in many geographical locations. Our large-scale 16S rRNA gene survey across three oceans revealed that the core microbiome of T. hoshinota included operational taxonomic units (OTUs) related to Prochloron, Endozoicomonas, Pseudospirillum, SAR116, Magnetospira, and Ruegeria. A Prochloron- related OTU was the most dominant cyanobacterium in T. hoshinota in the western Pacific Ocean, South China Sea, and Indian Ocean. The complete metagenome-assembled genome of the Prochloron-related cyanobacterium and our pigment analysis revealed that this bacterium had phycobiliproteins and phycobilins and lacked chlorophyll b, inconsistent with the iconic definition of Prochloron. Furthermore, the phylogenetic analyses based on 16S rRNA genes and 120 single-copy genes demonstrated that the bacterium was phylogenetically distinct to Prochloron, strongly suggesting that it should be a sister taxon to Prochloron; we therefore proposed this symbiotic cyanobacterium as a novel species under a new genus: Candidatus Paraprochloron terpiosii. With the recovery of the complete genome, we characterized the metabolic potentials of the novel cyanobacterium in carbon and nitrogen cycling and proposed a model for the interaction between Ca. Pp. terpiosi LD05 and T. hoshinota. In addition, comparative genomics analysis revealed that Ca. Paraprochloron and Prochloron showed distinct features in transporter systems and DNA replication.ImportanceThe finding that one species predominates cyanobacteria in T. hoshinota from different geographic locations indicates that this sponge and Ca. Pp. terpiosi LD05 share a tight relationship. This study builds the foundation for T. hoshinota’s microbiome and paves a way for understanding the ecosystem, invasion mechanism, and causes of outbreak of this coral-killing sponge. Also, the first Prochloron-related complete genome enables us to study this bacterium with molecular approaches in the future and broadens our knowledge of the evolution of symbiotic cyanobacteria.

Phalaenopsis (Phal.) orchids including white, yellow, and purple flowers are some of the most important commercial orchids worldwide. These flowering plants can be considered to be promising sources of antioxidants since several medicinal orchids were shown to have potential antioxidant activities. The antioxidant activities and several secondary metabolite compounds of the methanolic extracts of four parts (the root, pedicel, leaf, and flower) of three hybrids of white (Phal. ‘City More’), yellow (Phal. ‘Sogo Meili’), and purple (Phal. ‘Queen Beer’) flowering orchids were investigated. Results showed that the highest levels of chlorophyll a and chlorophyll b were respectively obtained in leaf extracts of white and purple orchids, whereas carotenoid showed the highest content in the flower extract of the yellow orchid. Among all tested extracts, flavonoids and anthocyanin demonstrated the highest levels in the flower extract of the purple orchid, whereas the highest level of polyphenols was observed in the flower extract of the yellow orchid. The leaf extract of the white orchid was the most effective extract with a 50% inhibitory concentration in the DPPH-scavenging activity assay, while the highest ferrous iron-chelating effect was observed in flower extracts of the yellow orchid and purple orchid, and the pedicel extract of the purple orchid. In the reducing power assay, the flower extract of the white orchid showed the most potent extract, followed by the leaf extract of the yellow orchid and the flower extract of the purple orchid. Relationships between flower colors and antioxidant activities of these orchids showed them to be potential sources of antioxidants for both medicinal use and stress-tolerance in these orchids.

Photosynthetic and transcriptomic characteristics of a chlorophyll (Chl) b-deficient mutant type 2b rice (ch14) were investigated in this study. The ultrastructure of chloroplast in ch14 demonstrated irregular chloroplast enhancement (loss of starch granules, indistinct membranes, and thinner grana). Ch14 had significantly lower carotenoid, Chl a, Chl b, and total Chl contents, but a higher ratio of Chl a to Chl b than a wide-type rice. 3,594 genes were differentially expressed in ch14, among which 309 transcription factors were related to Chl degradation and biosynthesis, chloroplast formations, and the photosynthesis capacity. PsbR, GSA-AT, PBGD, PPOX, MgMT, and POR genes were down-regulated, reducing Chl content and photosynthetic capacity in the ch14. This study suggests that Chl degradation may be attributed to abnormal chloroplast development and down-regulation of gene expression in the common pathway and Mg branch and the rise in Chl a to Chl b ratio may be involved in the alternative Chl b degradation pathway.

Photosynthetic properties and transcriptomic profiles of green and white sectors of Ficus microcarpa (c.v. milky stripe fig) leaves were examined in naturally variegated plants. An anatomic analysis indicated that chloroplasts of the white sectors contained a higher abundance of starch granules and lacked stacked thylakoids. Moreover, no photosynthetic rate was detected in the white sectors. Transcriptome profile and differential expressed gene (DEG) analysis showed that genes encoding PSII core proteins were down-regulated in the white sectors. In genes related to chlorophyll metabolism, no DEGs were identified in the biosynthesis pathway of chlorophyll. However, genes encoding the first step of chlorophyll breakdown were up-regulated. The repression of genes involved in N-assimilation suggests that the white sectors were deprived of N. The mutation in the transcription factor mitochondrial transcription termination factor (mTERF) suggests that it induces colorlessness in leaves of the milky stripe fig.

Arsenic contamination of tube well water has become the greatest health threat to the people. This cross-sectional analytic study aimed to find out the prevalence of arsenic contaminated wells in selected areas of Kyaunggon Township, to increase the arsenic awareness and to construct the low-cost arsenic reducing Gravel Sand Filter (GSF) for household use. The water samples were tested for arsenic and other parameters. About 66% (63/96) tube wells of depth between 12 to 183 meters had arsenic concentration more than 10 ppb and moreover 42 out of 63 tube wells had depth between 30 to 90 meters. Therefore, this depth range should be avoided for tube well construction in that area. About 67.7 % (65/96) had iron concentration more than 0.3 ppm, 74 % (71/96) had manganese concentration more than 0.4 ppm and 4.1 % (4/96) had phosphate concentration more than 4 ppm according to WHO drinking water quality guideline. These results were disseminated to basic health staff, teachers and students from respective areas. GSF was constructed and demonstrated to villagers. Widely using of this removal method in arsenic contaminated areas will partly contribute towards the safe water supply and promote the community health.

Photosynthetic properties and transcriptomic profiles of green and white sectors of Ficus microcarpa (c.v. milky stripe fig) leaves were examined in naturally variegated plants. An anatomic analysis indicated that chloroplasts of the white sectors contained a higher abundance of starch granules and lacked stacked thylakoids. Moreover, no photosynthetic rate was detected in the white sectors. Transcriptome profile and differential expressed gene (DEG) analysis showed that genes encoding PSII core proteins were down-regulated in the white sectors. In genes related to chlorophyll metabolism, no DEGs were identified in the biosynthesis pathway of chlorophyll. However, genes encoding the first step of chlorophyll breakdown were up-regulated. The repression of genes involved in N-assimilation suggests that the white sectors were deprived of N. The mutation in the transcription factor mitochondrial transcription termination factor (mTERF) suggests that it induces colorlessness in leaves of the milky stripe fig.

Anthocyanins (Ants) are water-soluble secondary metabolites that are responsible for red colour of plant leaves. To determine photosynthetic pigments, 80% acetone was used to extract Ants from Ant-containing leaves of test plants. However, using the 80% acetone extraction method can lead to interference between chlorophylls (Chls) and Ants. Porphyrins, such as protoporphyrin IX (PPIX), Mg-protoporphyrin IX (MgPP), and protochlorophyllide (Pchlide), are Chl biosynthetic intermediates and demonstrate photospectrometric characteristics similar to those of Chl. Although the ether/water extraction method was able to remove Ants interference when detecting porphyrins, the porphyrins extraction efficiency was lower than that of the 80% acetone extraction method. Low Ants levels interfered with individual porphyrin ratios, and the extent of the effect was correlated with Ants concentrations. We developed the three equations could eliminate interference by Ants when determining the porphyrin molecular percentage (%) and were comprehensively applied to all tested species of Ants-containing leaves.

Background Insect galls are atypical plant tissues induced by the invasion of insects. Compared to the host leaf, gall tissues lose photosynthetic ability, but have higher soluble sugar content. Although the physiological and biochemical regulation of gall tissues have been demonstrated, the mechanism of genetic regulation has only been analyzed in few studies. Results In this study, the transcriptome of cup-shaped galls and its host leaf were de novo assembled. Cellular functional enrichment and differentially expressed gene groups in the gall tissues were analyzed. The genes associated with primary metabolism, including photosynthesis, cell wall turnover, and sugar degradation, were expressed differently in galls and leaves. The examination of gene expression demonstrated that the genes involved in brassinosteroid synthesis and responses exhibited a remarkable modulation in cup-shaped galls, suggesting a potential role of steroid hormones in regulating gall development. Conclusions This study revealed the genetic responses, including those involved in source-sink reallocation and phytohormone metabolism, of galls induced by a dipteran insect.

Staphylococcus aureusbacteraemia (SAB) remains a complex disease with a high associated morbidity and mortality, especially when it is able to establish an occult nidus safe from antimicrobial eradication. Without rapid identification and intervention, the nidus can cause persistent relapse of disease, morbidity and mortality. Having a high clinical suspicion for the foci of occult S. aureus is important, and awareness of potential sites of infection is critical and can be life-saving. We present a unique case of a 65-year-old man with end-stage renal disease receiving haemodialysis who developed septic shock from SAB. Despite 18 days of appropriate antibiotics, the patient had persistent high-grade bacteraemia until his gall bladder was ultimately percutaneously drained. The day after drainage, he cleared his blood cultures, although he ultimately passed away as he decided to transition his care to focus on comfort measures.

Immunosuppressive agents predispose patients to legionnaire's disease. Patients receiving tumor necrosis factor antagonists are generally not severely immunocompromised by the underlying disease. In patients with malignancy receiving immunosuppressive therapies, it is difficult to balance the underlying disease versus the therapy used. Transplant recipients are often on multiple drugs, including immunosuppressants. It seems that immunosuppressive drugs add to the risk for legionella infection. The index of suspicion should be high for legionella infection early during a compatible clinical syndrome. The control of Legionella species and prevention of transmission should be the foremost goal in protecting susceptible populations from Legionnaire's disease.

To investigate whether Na+uptake by zebrafish is dependent on NH4+excretion, a scanning ion-selective electrode technique was applied to measure Na+and NH4+gradients at the yolk-sac surface of zebrafish larvae. Low-Na+acclimation induced an inward Na+gradient (uptake), and a combination of low Na+and high NH4+induced a larger inward Na+gradient. When measuring the ionic gradients, raising the external NH4+level (5 mM) blocked NH4+excretion and Na+uptake; in contrast, raising the external Na+level (10 mM) simultaneously enhanced Na+uptake and NH4+excretion. The addition of MOPS buffer (5 mM), which is known to block NH4+excretion, also suppressed Na+uptake. These results showed that Na+uptake and NH4+excretion by larval skin are associated when ambient Na+level is low. Knockdown of Rhcg1 translation with morpholino-oligonucleotides decreased both NH4+excretion and Na+uptake by the skin and Na+content of whole larvae. Knockdown of nhe3b translation or inhibitor (5-ethylisopropyl amiloride) treatment also decreased both the NH4+excretion and Na+uptake. This study provides loss-of-function evidence for the involvement of Rhcg1 and NHE3b in the ammonium-dependent Na+uptake mechanism in zebrafish larvae subjected to low-Na+water.

A noninvasive scanning ion-selective electrode technique (SIET) was applied to measure Cl−transport at individual mitochondrion-rich cells (MRCs) in the skin of euryhaline tilapia ( Oreochromis mossambicus) larvae. In seawater (SW)-acclimated larvae, outward Cl−gradients (20∼80 mM higher than the background) were measured at the surface, indicating a secretion of Cl−from the skin. By serial probing over the surface of MRCs and adjacent keratinocytes (KCs), a significant outward flux of Cl−was detected at the apical opening (membrane) of MRCs. Treatment with 100 μM ouabain or bumetanide inhibited the Cl−secretion by ∼75%. In freshwater (FW)-acclimated larvae, a lower level of outward Cl−gradients (0.2∼1 mM) was measured at the skin surface. Low-Cl−water (+-Cl−cotransporter (NCC) immunoreactivity of MRCs in the larval skin. An inward flux of Cl−was detected when probing the exterior surface of a group of MRCs (convex-MRCs) that express the NCC. An NCC inhibitor (100 μM metolazone) reduced the flux by ∼90%. This study provides direct and convincing evidence for Cl−transport by MRCs of SW- and FW-acclimated euryhaline tilapia and the involvement of an apical NCC in Cl−uptake of MRCs of FW-acclimated fish.

The mechanism of ammonia excretion in freshwater teleosts is not well understood. In this study, scanning ion-selective electrode technique was applied to measure H+and NH4+fluxes in specific cells on the skin of zebrafish larvae. NH4+extrusion was relatively high in H+pump-rich cells, which were identified as the H+-secreting ionocyte in zebrafish. Minor NH4+extrusion was also detected in keratinocytes and other types of ionocytes in larval skin. NH4+extrusion from the skin was tightly linked to acid secretion. Increases in the external pH and buffer concentration (5 mM MOPS) diminished H+and NH4+gradients at the larval surface. Moreover, coupled decreases in NH4+and H+extrusion were found in larvae treated with an H+-pump inhibitor (bafilomycin A1) or H+-pump gene ( atp6v1a) knockdown. Knockdown of Rhcg1 with morpholino-oligonucleotides also decreased NH4+excretion. This study demonstrates ammonia excretion in epithelial cells of larval skin through an acid-trapping mechanism, and it provides direct evidence for the involvement of the H+pump and an Rh glycoprotein (Rhcg1) in ammonia excretion.