Inorganic polyphosphate: essential for growth and survival.

Inorganic polyphosphate (Poly P) is a polymer of tens to hundreds of phosphate residues linked by "high-energy" phosphoanhydride bonds as in ATP. Found in abundance in all cells in nature, it is unique in its likely role in the origin and survival of species. Here, we present extensive evidence that the remarkable properties of Poly P as a polyanion have made it suited for a crucial role in the emergence of cells on earth. Beyond that, Poly P has proved in a variety of ways to be essential for growth of cells, their responses to stresses and stringencies, and the virulence of pathogens. In this review, we pay particular attention to the enzyme, polyphosphate kinase 1 (Poly P kinase 1 or PPK1), responsible for Poly P synthesis and highly conserved in many bacterial species, including 20 or more of the major pathogens. Mutants lacking PPK1 are defective in motility, quorum sensing, biofilm formation, and virulence. Structural studies are cited that reveal the conserved ATP-binding site of PPK1 at atomic resolution and reveal that the site can be blocked with minute concentrations of designed inhibitors. Another widely conserved enzyme is PPK2, which has distinctive kinetic properties and is also implicated in the virulence of some pathogens. Thus, these enzymes, absent in yeast and animals, are novel attractive targets for treatment of many microbial diseases. Still another enzyme featured in this review is one discovered in Dictyostelium discoideum that becomes an actin-like fiber concurrent with the synthesis, step by step, of a Poly P chain made from ATP. The Poly P-actin fiber complex, localized in the cell, lengthens and recedes in response to metabolic signals. Homologs of DdPPK2 are found in pathogenic protozoa and in the alga Chlamydomonas. Beyond the immediate relevance of Poly P as a target for anti-infective drugs, a large variety of cellular operations that rely on Poly P will be considered.

Entamoeba histolytica: In Silico and In Vitro Oligomerization of EhHSTF5 Enhances Its Binding to the HSE of the EhPgp5 Gene Promoter.

Throughout its lifecycle, Entamoeba histolytica encounters a variety of stressful conditions. This parasite possesses Heat Shock Response Elements (HSEs) which are crucial for regulating the expression of various genes, aiding in its adaptation and survival. These HSEs are regulated by Heat Shock Transcription Factors (EhHSTFs). Our research has identified seven such factors in the parasite, designated as EhHSTF1 through to EhHSTF7. Significantly, under heat shock conditions and in the presence of the antiamoebic compound emetine, EhHSTF5, EhHSTF6, and EhHSTF7 show overexpression, highlighting their essential role in gene response to these stressors. Currently, only EhHSTF7 has been confirmed to recognize the HSE as a promoter of the EhPgp5 gene (HSE_EhPgp5), leaving the binding potential of the other EhHSTFs to HSEs yet to be explored. Consequently, our study aimed to examine, both in vitro and in silico, the oligomerization, and binding capabilities of the recombinant EhHSTF5 protein (rEhHSTF5) to HSE_EhPgp5. The in vitro results indicate that the oligomerization of rEhHSTF5 is concentration-dependent, with its dimeric conformation showing a higher affinity for HSE_EhPgp5 than its monomeric state. In silico analysis suggests that the alpha 3 α-helix (α3-helix) of the DNA-binding domain (DBD5) of EhHSTF5 is crucial in binding to the major groove of HSE, primarily through hydrogen bonding and salt-bridge interactions. In summary, our results highlight the importance of oligomerization in enhancing the affinity of rEhHSTF5 for HSE_EhPgp5 and demonstrate its ability to specifically recognize structural motifs within HSE_EhPgp5. These insights significantly contribute to our understanding of one of the potential molecular mechanisms employed by this parasite to efficiently respond to various stressors, thereby enabling successful adaptation and survival within its host environment.

BFNB Enhances Hair Growth in C57BL/6 Mice through the Induction of EGF and FGF7 Factors and the PI3K-AKT-ß-Catenin Pathway.

The objective of this study was to investigate the potential effects of a formulation derived from the bioactive fraction of nanostructured Bacopa procumbens (BFNB) on the promotion of hair growth in C57BL/6 mice. The characterization of the follicular phases and histomorphological analysis showed that the topical application of the formulation for 15 days significantly increased pigmentation and hair growth on the dorsum and head of the mice. Additionally, an acceleration of the follicular cycle phases was observed, along with an increase in the number of follicles, hair length, and diameter, compared to mice treated with minoxidil. In silico analysis and molecular characterization demonstrated that BFNB enhances the expression of epidermal growth factor (EGF) and fibroblast growth factor 7 (FGF7), activating the PI3K-AKT-ß-catenin signaling pathway, as well as the expression of PCNA, KI-67, Cyclin D1, and Cyclin E, regulating the cell cycle and cell proliferation, crucial events for hair regeneration. Our results strongly suggest the utility of BFNB as a therapeutic alternative to stimulate hair growth and promote hair health.

Polyphenolic Compounds Nanostructurated with Gold Nanoparticles Enhance Wound Repair.

Gold nanoparticles (AuNPs) have been used in a wide range of applications, conferring to bio-molecules diverse properties such as delivery, stabilization, and reduction of the adverse effects of drugs or plant extracts. Polyphenolic compounds from Bacopa procumbens (B. procumbens) (BP) can modulate proliferation, adhesion, migration, and cell differentiation, reducing the artificial scratch area in fibroblast cultures and promoting wound healing in an in vivo model. Here, chemically synthesized AuNPs conjugated with BP (AuNP-BP) were characterized using UV-Vis, ATR-FTIR, DLS, zeta-potential, and TEM analysis. The results showed an overlap of the FTIR spectra of the polyphenolic compounds from B. procumbens adhered to the surface of the AuNPs. UV-vis analysis indicated that the average size of the AuNP-BP was 28 nm, while DLS analysis showed a size of 44.58 nm and, by TEM, a size of 16.5 nm with an icosahedral morphology was observed. These measurements suggest an increase in the size of the nanoparticles after conjugation with BP, compared to the sizes of 9 nm, 44.51 nm, and 14.17 nm for the unconjugated AuNPs, respectively. Furthermore, the zeta potential of the AuNPs, which was originally -36.3 ± 12.3 mV shifted to -18.2 ± 7.02 mV after conjugation with BP, indicating improved stability of the nanoparticles. Enhancement of the wound healing effect was evaluated by morphometric, histochemical, and FTIR changes in a rat wound excision model. Results showed that the nanoconjugation process reduced the BP concentrations by 100-fold to have the same wound healing effect as BP alone. Besides, histological and FTIR spectroscopy analyses demonstrated that AuNP-BP treatment exhibited better macroscopical performance, showing a reduction in inflammatory cells and an increased synthesis and improved organization of collagen fibers.

Characterization of Polyphenolic Compounds from Bacopa procumbens and Their Effects on Wound-Healing Process.

Wounds represent a medical problem that contributes importantly to patient morbidity and to healthcare costs in several pathologies. In Hidalgo, Mexico, the Bacopa procumbens plant has been traditionally used for wound-healing care for several generations; in vitro and in vivo experiments were designed to evaluate the effects of bioactive compounds obtained from a B. procumbens aqueous fraction and to determine the key pathways involved in wound regeneration. Bioactive compounds were characterized by HPLC/QTOF-MS, and proliferation, migration, adhesion, and differentiation studies were conducted on NIH/3T3 fibroblasts. Polyphenolic compounds from Bacopa procumbens (PB) regulated proliferation and cell adhesion; enhanced migration, reducing the artificial scratch area; and modulated cell differentiation. PB compounds were included in a hydrogel for topical administration in a rat excision wound model. Histological, histochemical, and mechanical analyses showed that PB treatment accelerates wound closure in at least 48 h and reduces inflammation, increasing cell proliferation and deposition and organization of collagen at earlier times. These changes resulted in the formation of a scar with better tensile properties. Immunohistochemistry and RT-PCR molecular analyses demonstrated that treatment induces (i) overexpression of transforming growth factor beta (TGF-ß) and (ii) the phosphorylation of Smad2/3 and ERK1/2, suggesting the central role of some PB compounds to enhance wound healing, modulating TGF-ß activation.

Glutaminase isoforms expression switches microRNA levels and oxidative status in glioblastoma cells.

BACKGROUND: Glutaminase isoenzymes GLS and GLS2 play apparently opposing roles in cancer: GLS acts as an oncoprotein, while GLS2 (GAB isoform) has context specific tumour suppressive activity. Some microRNAs (miRNAs) have been implicated in progression of tumours, including gliomas. The aim was to investigate the effect of GLS and GAB expression on both miRNAs and oxidative status in glioblastoma cells. METHODS: Microarray profiling of miRNA was performed in GLS-silenced LN229 and GAB-transfected T98G human glioblastoma cells and their wild-type counterparts. Results were validated by real-time quantitative RT-PCR. Oxidative status and antioxidant enzymes were determined by spectrophotometric or fluorescence assays in GLS-silenced LN229 and T98G, and GAB-transfected LN229 and T98G. RESULTS: MiRNA-146a-5p, miRNA-140-3p, miRNA-21-5p, miRNA-1260a, and miRNA-92a-3p were downregulated, and miRNA-1246 was upregulated when GLS was knocked down. MiRNA-140-3p, miRNA-1246, miRNA-1260a, miRNA-21-5p, and miRNA-146a-5p were upregulated when GAB was overexpressed. Oxidative status (lipid peroxidation, protein carbonylation, total antioxidant capacity, and glutathione levels), as well as antioxidant enzymes (catalase, superoxide dismutase, and glutathione reductase) of silenced GLS glioblastoma cells and overexpressed GAB glioblastoma cells significantly changed versus their respective control glioblastoma cells. MiRNA-1246, miRNA-1260a, miRNA-146a-5p, and miRNA-21-5p have been characterized as strong biomarkers of glioblastoma proliferation linked to both GLS silencing and GAB overexpression. Total glutathione is a reliable biomarker of glioblastoma oxidative status steadily associated to both GLS silencing and GAB overexpression. CONCLUSIONS: Glutaminase isoenzymes are related to the expression of some miRNAs and may contribute to either tumour progression or suppression through certain miRNA-mediated pathways, proving to be a key tool to switch cancer proliferation and redox status leading to a less malignant phenotype. Accordingly, GLS and GAB expression are especially involved in glutathione-dependent antioxidant defence.

Capsicum annuum (hot pepper): An ancient Latin-American crop with outstanding bioactive compounds and nutraceutical potential. A review.

Hot pepper (Capsicum annuum) fruits, usually termed as chili, have been used since ancient times as food vegetables, flavoring ingredients, natural colorants, and in traditional medicines. Nowadays, a wide variation of sweet and pungent peppers are consumed worldwide in a large variety of forms. Interestingly, the most important hot pepper at the global level in commercial terms is C. annuum with a high number of varieties. This review compares C. annuum to other Capsicum species for plant agronomic traits, biochemical composition, the content of capsaicin and capsaicinoids and their nutraceutical and medical potentialities, and the effects of processing on quality and key components of the fruit, among other aspects. Chili contains important levels of pigments (i.e., chlorophyll, anthocyanin, and lutein) with potential health benefits; it also contains additional outstanding health-promoting chemical compounds, such as vitamins, minerals, flavonoids, carotenoids, and capsaicinoids, in general. And capsaicin, the major active compound responsible for the pungent taste of these species has been proven to have a positive role in health. We report here on how dietary chili and capsaicinoids consumption, especially capsaicin, are involved in body weight reduction and their potential antiobesity effects, in urinary disorders, as well as antioxidants, antimicrobial, anticancer, and analgesic capacity. Selected characteristics of processing for the fruit preservation on its quality and content of these compounds are described as well. However, additional clinical research on the mechanism of action and efficacy of frequent capsaicinoid consumption on human health is needed.

Dual role of inorganic polyphosphate in cardiac myocytes: The importance of polyP chain length for energy metabolism and mPTP activation.

We have previously demonstrated that inorganic polyphosphate (polyP) is a potent activator of the mitochondrial permeability transition pore (mPTP) in cardiac myocytes. PolyP depletion protected against Ca2+-induced mPTP opening, however it did not prevent and even exacerbated cell death during ischemia-reperfusion (I/R). The central goal of this study was to investigate potential molecular mechanisms underlying these dichotomous effects of polyP on mitochondrial function. We utilized a Langendorff-perfused heart model of I/R to monitor changes in polyP size and chain length at baseline, 20 min no-flow ischemia, and 15 min reperfusion. Freshly isolated cardiac myocytes and mitochondria from C57BL/6J (WT) and cyclophilin D knock-out (CypD KO) mice were used to measure polyP uptake, mPTP activity, mitochondrial membrane potential, respiration and ATP generation. We found that I/R induced a significant decrease in polyP chain length. We, therefore, tested, the ability of synthetic polyPs with different chain length to accumulate in mitochondria and induce mPTP. Both short and long chain polyPs accumulated in mitochondria in oligomycin-sensitive manner implicating potential involvement of mitochondrial ATP synthase in polyP transport. Notably, only short-chain polyP activated mPTP in WT myocytes, and this effect was prevented by mPTP inhibitor cyclosprorin A and absent in CypD KO myocytes. To the contrary, long-chain polyP suppressed mPTP activation, and enhanced ADP-linked respiration and ATP production. Our data indicate that 1) effect of polyP on cardiac function strongly depends on polymer chain length; and 2) short-chain polyPs (as increased in ischemia-reperfusion) induce mPTP and mitochondrial uncoupling, while long-chain polyPs contribute to energy generation and cell metabolism.

Influence of age on tolerability, safety and effectiveness of subdermal contraceptive implants.

The use of long-acting contraceptive methods is on the rise. The aim of this study was to describe the main variables (effectiveness, tolerability, menstrual bleeding) associated with the use of subdermal contraceptive implants and to investigate the influence of age on these variables. This was a descriptive, retrospective, observational study of 221 cases of contraceptive implants inserted at a Spanish hospital between 2006 and 2015. The mean age of implant users was 31.2 ± 7.5 years. Effectiveness was 100% and good tolerability was recorded for 86.5%. Infrequent bleeding was the most common bleeding pattern, followed by amenorrhoea. Of the 221 implants inserted, 47.5% were removed. The main reasons were expiration (54.3%) and discomfort due to bleeding alterations and other adverse effects (25.7%). Nulliparity and weight gain were significantly associated with an increased probability of implant removal. This study shows that implants were highly effective, safe and well-tolerated in our population. The age of users had no influence on any of the study variables analysed. Impact Statement What is already known on this subject? Subdermal contraceptive implants are long-acting reversible contraceptives which are both safe and effective. What do the results of this study add? The age of users had no influence on any of the study variables analysed. Nulliparity and weight gain were significantly associated with an increased probability of implant removal. What are the implications of these findings for clinical practice and/or further research? Subdermal contraceptive implants were a safe and effective long-acting progestin contraceptive method for women from all age groups in our series because no significant age-related differences were observed for the tolerability, vaginal bleeding patterns, the effectiveness, the adverse effects or any other variables.

Initial experience with golimumab in clinical practice for ulcerative colitis.

BACKGROUND: Golimumab is a TNF-blocking agent indicated as a second-line therapy in ulcerative colitis. PURPOSE: To research the effectiveness and safety of golimumab in patients with ulcerative colitis in clinical practice. METHODS: Retrospective study of the effectiveness and safety of golimumab in patients with ulcerative colitis. All patients received golimumab 200 mg subcutaneously at week 0, and golimumab 100 mg subcutaneously at week 2. After the induction treatment, each patient received 50 mg sc. every 4 weeks in patients with body weight less than 80 kg, and 100 mg every 4 weeks in patients with body weight greater than or equal to 80 kg. RESULTS: Study of a group of 23 ulcerative colitis patients, 7 of whom were naive to any anti-TNF therapy, and 16 patients who had previously been treated with an anti-TNF agent other than golimumab (non-naive patients). The average treatment time with golimumab was 14.3 weeks. Globally, withdrawal of corticosteroids was observed in 74% of cases. Clinical response was observed in 85.5% of patients who had not received biological treatment previously, and in patients who had previously received biological treatment the response rate was 75%. CONCLUSIONS: In this short study, golimumab seems to be an alternative treatment in naive and non-naive anti-TNF ulcerative colitis patients. It is also a safe therapy, given that there were no adverse effects in the patients studied.

Association of haplotypes of the TLR8 locus with susceptibility to Crohn's and Behçet's diseases.

OBJECTIVES: The aim of this study was to investigate the role of the TLR8, a mediator of innate inflammatory response, in susceptibility to two immune-mediated disorders characterised by dysregulation of the immune response, Crohn's and Behçet's diseases (CD and BD). METHODS: A total of 844 CD, 371 BD patients and 1385 controls were genotyped in 8 tag single nucleotide polymorphisms (tSNPs) in the locus TLR8 (chromosome X). All these tSNPs have a minor allele frequency greater than 0.05 in the Caucasian population. RESULTS: The rs2407992 and the rs5744067 were associated with susceptibility to BD and CD, respectively (OR=1.34, 95%CI=1.10-1.62, p=0.0025 and OR=0.82, 95%CI=0.68-0.99, p=0.045, respectively). Although after stratification by gender, statistically significant differences in the distribution of the aforementioned SNPs were only observed in the females groups (BD OR=1.31, 95%CI=1.06-1.64, p=0.012 and CD OR=0.84, 95%CI=0.72-0.98, p=0.044) the trend was similar among males. Since the rs5744067 and rs2407992 are located in the same linkage disequilibrium block, we performed a haplotypic analysis by combination of the tSNPs. One haplotype (H1) was identified as a protective factor in BD (OR=0.75, 95%CI=0.62-0.90, p=0.0027) and another (H2) as a protective factor in CD (OR=0.78, 95%CI=0.64-094, p=0.0102). No statistically significant differences in the mean of the levels of expression attributable to the haplotype variants were found in the in silico analysis performed. CONCLUSIONS: Our results suggest a relationship between the TLR8 and the susceptibility to CD and BD. Nevertheless, these differences could not be imputed to the levels of expression.

Response to Infliximab in Crohn's Disease: Genetic Analysis Supporting Expression Profile.

Substantial proportion of Crohn's disease (CD) patients shows no response or a limited response to treatment with infliximab (IFX) and to identify biomarkers of response would be of great clinical and economic benefit. The expression profile of five genes (S100A8-S100A9, G0S2, TNFAIP6, and IL11) reportedly predicted response to IFX and we aimed at investigating their etiologic role through genetic association analysis. Patients with active CD (350) who received at least three induction doses of IFX were included and classified according to IFX response. A tagging strategy was used to select genetic polymorphisms that cover the variability present in the chromosomal regions encoding the identified genes with altered expression. Following genotyping, differences between responders and nonresponders to IFX were observed in haplotypes of the studied regions: S100A8-S100A9 (rs11205276* G/rs3014866* C/rs724781* C/rs3006488* A; P = 0.05); G0S2 (rs4844486* A/rs1473683* T; P = 0.15); TNFAIP6 (rs11677200* C/rs2342910* A/rs3755480* G/rs10432475* A; P = 0.10); and IL11 (rs1126760* C/rs1042506* G; P = 0.07). These differences were amplified in patients with colonic and ileocolonic location for all but the TNFAIP6 haplotype, which evidenced significant difference in ileal CD patients. Our results support the role of the reported expression signature as predictive of anti-TNF outcome in CD patients and suggest an etiological role of those top-five genes in the IFX response pathway.

[Spontaneous hemoperitoneum and clear cell tumor of ovary]. / Hemoperitoneo espontáneo y carcinoma ovárico de células claras.

UNLABELLED: Hemoperitoneum is a rare cause of acute abdomen, which is usually due to liver, spleen, hematologic and vascular causes. We should consider gynecological origin in women in reproductive age, being a rare etiology in postmenopausal. CLINICAL CASE: We report the case of a spontaneous hemoperitoneum in a postmenopausal woman as the first manifestation of an ovarian tumor, with exceptional pathological lineage: clear cell carcinoma. Hemoperitoneum is a suspected diagnosis before clinical symptoms of hypovolemic shock and acute abdomen, with decrease in hemoglobin. To treating underlying cause, which in this case was surgical, it's important the clinical suspect and the appropriate hemodynamic support of the patient. Despite the resolution of the acute, it is particularly important the subsequent clinical monitoring of the patient by the peculiarities of this type of tumors.

[Non-surgical management of rectovaginal fistula: a case report]. / Tratamiento no quirúrgico de la fístula rectovaginal. A propósito de un caso.

BACKGROUND: The rectovaginal fistula is a rare disease whose treatment is extremely difficult. OBJECTIVE: To present the expectant management of rectovaginal fistula as an alternative to surgery for those cases in which the surgical risk is not an acceptable option. CLINICAL CASE: We report the case of a rectovaginal fistula in an 85-year-old woman with significant comorbidity that avoided the performance of any surgical technique. CONCLUSION: In patients whose surgical risk does not exceed the benefits, non-surgical management would be an option of treatment of rectovaginal fistula.

Early azathioprine therapy is no more effective than placebo for newly diagnosed Crohn's disease.

BACKGROUND & AIMS: A small placebo-controlled trial reported the efficacy of mercaptopurine therapy for children newly diagnosed with Crohn's disease, yet little is known about the efficacy of early thiopurine therapy in adults. METHODS: We performed a prospective double-blind trial of adult patients with a recent (<8 weeks) diagnosis of Crohn's disease. Patients were randomly assigned to groups given azathioprine (2.5 mg · kg(-1) · day(-1), n = 68) or placebo (n = 63) at 31 hospitals from February 2006 to September 2009. Corticosteroids but no other concomitant medications were allowed for control of disease activity. The primary measure of efficacy was sustained corticosteroid-free remission. RESULTS: After 76 weeks of treatment, 30 patients treated with azathioprine (44.1%) and 23 given placebo (36.5%) were in sustained corticosteroid-free remission (difference of 7.6%; 95% confidence interval, -9.2 to 24.4%; P = .48). The rates of relapse (defined as Crohn's Disease Activity Index score >175) and corticosteroid requirements were similar between groups. A post hoc analysis of relapse, defined as a Crohn's Disease Activity Index score >220, showed lower relapse rates in the azathioprine group than in the placebo group (11.8% vs 30.2%; P = .01). Serious adverse events occurred in 14 patients in the azathioprine group (20.6%) and 7 in the placebo group (11.1%) (P = .16). A larger percentage of patients in the azathioprine group had adverse events that led to study drug discontinuation (20.6%) than in the placebo group (6.35%) (P = .02). CONCLUSIONS: In a study of adults with Crohn's disease, early azathioprine therapy was no more effective than placebo to achieve sustained corticosteroid-free remission but was more effective in preventing moderate to severe relapse in a post hoc analysis. EudraCT 2005-001186-34.

[Diagnosis and treatment of hemophilia A acquired during postpartum ]. / Diagnóstico y tratamiento de hemofilia A adquirida durante el posparto.

Acquired hemophilia A is a truly exceptional hemorrhagic diathesis, that consists of the emergence of polyclonal autoantibodies (inhibitor) IgG-type (subclasses 1 and 4, in most cases) against the coagulant function of the circulating factor VIII, which acts in the domains C2, A2 and A3 of the molecule, thus interfering their interaction with the factor IXa, the phospholipids and the Von Willebrand factor. Its morbidity and mortality are high, but nevertheless its low incidence (1-1.5 cases per million population per year) is the most frequent autoimmune disorder. This paper reports the clinical case of two patients; the first one, 36 years old, who the tenth day of postpartum required re-entry due to a diagnosis of hematoma of the abdominal wall that was surgically drained twice. The patient of case 2 was 39 years old and at six days of postpartum went to the emergency room due to bleeding, she was underwent to curettage and therapeutic transfusion of 3 UCH. Because of the persistence of bleeding, which was not possible to control with medical treatment and conservative measures, therapeutic hysterectomy was performed, with blood transfusion later. Due to the hemorrhagic complications of this condition and the serious clinical consequences derived from them, it is important to establish an early diagnosis; it is therefore critical to know the existence of this very rare disease to be able to avoid its consequences.

Identification of modules and key genes associated with breast cancer subtypes through network analysis.

Breast cancer is the most common malignancy in women around the world. Intratumor and intertumoral heterogeneity persist in mammary tumors. Therefore, the identification of biomarkers is essential for the treatment of this malignancy. This study analyzed 28,143 genes expressed in 49 breast cancer cell lines using a Weighted Gene Co-expression Network Analysis to determine specific target proteins for Basal A, Basal B, Luminal A, Luminal B, and HER2 ampl breast cancer subtypes. Sixty-five modules were identified, of which five were characterized as having a high correlation with breast cancer subtypes. Genes overexpressed in the tumor were found to participate in the following mechanisms: regulation of the apoptotic process, transcriptional regulation, angiogenesis, signaling, and cellular survival. In particular, we identified the following genes, considered as hubs: IFIT3, an inhibitor of viral and cellular processes; ETS1, a transcription factor involved in cell death and tumorigenesis; ENSG00000259723 lncRNA, expressed in cancers; AL033519.3, a hypothetical gene; and TMEM86A, important for regulating keratinocyte membrane properties, considered as a key in Basal A, Basal B, Luminal A, Luminal B, and HER2 ampl breast cancer subtypes, respectively. The modules and genes identified in this work can be used to identify possible biomarkers or therapeutic targets in different breast cancer subtypes.

Role of polyphosphate in thermophilic Synechococcus sp. from microbial mats.

Synechococcus OS-B', a thermophilic unicellular cyanobacterium, recently isolated from the microbial mats in Octopus Spring (Yellowstone National Park), induces a suite of genes, including phosphatases and transporters, in response to phosphorus (P) starvation. Here we describe two different approaches to examine the ability of Synechococcus OS-B' to synthesize and break down polyphosphate (poly P), a key storage compound in many prokaryotes. First, we developed a transformation protocol to create mutants in the polyphosphate kinase (ppk), the major enzyme responsible for the synthesis of poly P. The ppk mutant exhibited a pleiotropic phenotype with defects in poly P accumulation, aberrant levels of Pho regulon transcripts, growth defects, and changes in cell size and exopolysaccharide levels, among others. Second, we measured transcripts of ppk and ppx (encoding the polyphosphatase) directly from mat samples and found that the levels varied dramatically over a diel cycle. We also used Western blot analysis to quantify levels of PPK and PPX and found that these enzymes differentially accumulated during the diel cycle. Levels of polyphosphate kinase peaked at night, while polyphosphatase levels were highest during the early morning hours. We hypothesize that the opposing activities of these two enzymes allow cells to store and utilize poly P to optimize growth over a diel cycle.

Biochemistry and molecular biology of carotenoid biosynthesis in chili peppers (Capsicum spp.).

Capsicum species produce fruits that synthesize and accumulate carotenoid pigments, which are responsible for the fruits' yellow, orange and red colors. Chili peppers have been used as an experimental model for studying the biochemical and molecular aspects of carotenoid biosynthesis. Most reports refer to the characterization of carotenoids and content determination in chili pepper fruits from different species, cultivars, varieties or genotypes. The types and levels of carotenoids differ between different chili pepper fruits, and they are also influenced by environmental conditions. Yellow-orange colors of chili pepper fruits are mainly due to the accumulation of α- and ß-carotene, zeaxanthin, lutein and ß-cryptoxanthin. Carotenoids such as capsanthin, capsorubin and capsanthin-5,6-epoxide confer the red colors. Chromoplasts are the sites of carotenoid pigment synthesis and storage. According to the most accepted theory, the synthesis of carotenoids in chili peppers is controlled by three loci: c1, c2 and y. Several enzymes participating in carotenoid biosynthesis in chili pepper fruits have been isolated and characterized, and the corresponding gene sequences have been reported. However, there is currently limited information on the molecular mechanisms that regulate this biosynthetic pathway. Approaches to gain more knowledge of the regulation of carotenoid biosynthesis are discussed.