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Abstract
Cell-free systems for gene expression have gained attention as platforms for the facile study of genetic circuits and as highly effective tools for teaching. Despite recent progress, the technology remains inaccessible for many in low- and middle-income countries due to the expensive reagents required for its manufacturing, as well as specialized equipment required for distribution and storage. To address these challenges, we deconstructed processes required for cell-free mixture preparation and developed a set of alternative low-cost strategies for easy production and sharing of extracts. First, we explored the stability of cell-free reactions dried through a low-cost device based on silica beads, as an alternative to commercial automated freeze dryers. Second, we report the positive effect of lactose as an additive for increasing protein synthesis in maltodextrin-based cell-free reactions using either circular or linear DNA templates. The modifications were used to produce active amounts of two high-value reagents: the isothermal polymerase Bst and the restriction enzyme BsaI. Third, we demonstrated the endogenous regeneration of nucleoside triphosphates and synthesis of pyruvate in cell-free systems (CFSs) based on phosphoenol pyruvate (PEP) and maltodextrin (MDX). We exploited this novel finding to demonstrate the use of a cell-free mixture completely free of any exogenous nucleotide triphosphates (NTPs) to generate high yields of sfGFP expression. Together, these modifications can produce desiccated extracts that are 203-424-fold cheaper than commercial versions. These improvements will facilitate wider use of CFS for research and education purposes.
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2
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Abstract
As the second year of the COVID-19 pandemic begins, it remains clear that a massive increase in the ability to test for SARS-CoV-2 infections in a myriad of settings is critical to controlling the pandemic and to preparing for future outbreaks. The current gold standard for molecular diagnostics is the polymerase chain reaction (PCR), but the extraordinary and unmet demand for testing in a variety of environments means that both complementary and supplementary testing solutions are still needed. This review highlights the role that loop-mediated isothermal amplification (LAMP) has had in filling this global testing need, providing a faster and easier means of testing, and what it can do for future applications, pathogens, and the preparation for future outbreaks. This review describes the current state of the art for research of LAMP-based SARS-CoV-2 testing, as well as its implications for other pathogens and testing. The authors represent the global LAMP (gLAMP) Consortium, an international research collective, which has regularly met to share their experiences on LAMP deployment and best practices; sections are devoted to all aspects of LAMP testing, including preanalytic sample processing, target amplification, and amplicon detection, then the hardware and software required for deployment are discussed, and finally, a summary of the current regulatory landscape is provided. Included as well are a series of first-person accounts of LAMP method development and deployment. The final discussion section provides the reader with a distillation of the most validated testing methods and their paths to implementation. This review also aims to provide practical information and insight for a range of audiences: for a research audience, to help accelerate research through sharing of best practices; for an implementation audience, to help get testing up and running quickly; and for a public health, clinical, and policy audience, to help convey the breadth of the effect that LAMP methods have to offer.
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Impact of Phyllantus niruri and Lactobacillus amylovorus SGL 14 in a mouse model of dietary hyperoxaluria. Benef Microbes 2020; 11:547-559. [PMID: 33032472 DOI: 10.3920/bm2020.0008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Hyperoxaluria is a pathological condition which affects long-term health of kidneys. The present study evaluates the impact of the combination of Lactobacillus amylovorus SGL 14 and the plant extract Phyllantus niruri (namely Phyllantin 14™) on dietary hyperoxaluria. Safety and efficacy of Phyllantin 14 have been evaluated in vivo. Mice C57BL6 fed a high-oxalate diet were compared to mice fed the same diet administered with Phyllantin 14 by gavage for 6 weeks. Control mice were fed a standard diet without oxalate. No adverse effects were associated to Phyllantin 14 supplementation, supporting its safety. Mice fed a high-oxalate diet developed significant hyperoxaluria and those administered with Phyllantin 14 showed a reduced level of urinary oxalate and a lower oxalate-to-creatinine ratio. Soluble and insoluble caecal oxalate were significantly lower in treated group, a finding in agreement with the colonisation study, i.e. mice were colonised with SGL 14 after 3 weeks. Microbiota analysis demonstrated that both oxalate diet and Phyllantin 14 can differently modulate the microbiota. In conclusion, our findings suggest that Phyllantin 14 supplementation represents a potential supportive approach for reducing urinary oxalate and/or for enhancing the efficacy of existing treatments.
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Publisher Correction: Genetic tool development in marine protists: emerging model organisms for experimental cell biology. Nat Methods 2020; 17:551. [PMID: 32296171 PMCID: PMC7200595 DOI: 10.1038/s41592-020-0828-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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5
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Germline BRCA2
K3326X and CHEK2
I157T mutations increase risk for sporadic pancreatic ductal adenocarcinoma. Int J Cancer 2019; 145:686-693. [PMID: 30672594 DOI: 10.1002/ijc.32127] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 11/23/2018] [Accepted: 12/05/2018] [Indexed: 02/05/2023]
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6
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Scanning Electron Microscopy of Ca-Alginate-Immobilized Aureobasidium Pullulans Grown Under Various Culture Conditions. Mycologia 2018. [DOI: 10.1080/00275514.1991.12026058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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7
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Purification and characterization of ribosomal proteins L27 and L30 having antimicrobial activity produced by the Lactobacillus salivarius SGL 03. J Appl Microbiol 2018; 124:398-407. [PMID: 29159916 DOI: 10.1111/jam.13646] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 10/31/2017] [Accepted: 11/13/2017] [Indexed: 01/31/2023]
Abstract
AIMS The aim of this study was to investigate the antimicrobial potential of proteins secreted by a new strain of Lactobacillus salivarius. METHODS AND RESULTS The secretome of L. salivarius SGL 03 strain was analysed by gel-assisted fractionation and MS/MS to identify low-molecular-mass proteins. This strategy allowed us to identify 10 secreted proteins. Then, a combination of heterologous expression and agar well diffusion was used to characterize them as to their antimicrobial activity, mechanisms of action and stability. Our findings indicate that L27 and L30 proteins of the 50S ribosomal subunit have antimicrobial activity against Streptococcus pyogenes, Streptococcus uberis and Enterococcus faecium. In addition, both proteins are bactericidal against S. pyogenes and maintain their antimicrobial activity after different protease treatments, at acidic pH, after heat treatment, and if stored in a refrigerated ambient at least at 4°C. CONCLUSIONS The overall results demonstrated that the L27 and L30 ribosomal proteins are of interest as new antimicrobial molecules to prevent the growth of S. pyogenes, S. uberis and E. faecium. SIGNIFICANCE AND IMPACT OF THE STUDY Our results provide the first insight into the extra-ribosomal activity of L27 and L30 secreted proteins of L. salivarius. This study demonstrated the capacity of L. salivarius SGL 03 to produce antimicrobial molecules and suggested this strain as a promising probiotic candidate.
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Abstract
Morphogenetic engineering is an emerging field that explores the design and implementation of self-organized patterns, morphologies, and architectures in systems composed of multiple agents such as cells and swarm robots. Synthetic biology, on the other hand, aims to develop tools and formalisms that increase reproducibility, tractability, and efficiency in the engineering of biological systems. We seek to apply synthetic biology approaches to the engineering of morphologies in multicellular systems. Here, we describe the engineering of two mechanisms, symmetry-breaking and domain-specific cell regulation, as elementary functions for the prototyping of morphogenetic instructions in bacterial colonies. The former represents an artificial patterning mechanism based on plasmid segregation while the latter plays the role of artificial cell differentiation by spatial colocalization of ubiquitous and segregated components. This separation of patterning from actuation facilitates the design-build-test-improve engineering cycle. We created computational modules for CellModeller representing these basic functions and used it to guide the design process and explore the design space in silico. We applied these tools to encode spatially structured functions such as metabolic complementation, RNAPT7 gene expression, and CRISPRi/Cas9 regulation. Finally, as a proof of concept, we used CRISPRi/Cas technology to regulate cell growth by controlling methionine synthesis. These mechanisms start from single cells enabling the study of morphogenetic principles and the engineering of novel population scale structures from the bottom up.
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Prediction of tumor response after neoadjuvant chemoradiotherapy in rectal cancer using 18fluorine-2-deoxy-d-glucose positron emission tomography-computed tomography: a prospective study. Ann Oncol 2016. [DOI: 10.1093/annonc/mdw335.38] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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10
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Orthogonal intercellular signaling for programmed spatial behavior. Mol Syst Biol 2016; 12:849. [PMID: 26814193 PMCID: PMC4731010 DOI: 10.15252/msb.20156590] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 11/19/2015] [Accepted: 11/23/2015] [Indexed: 12/31/2022] Open
Abstract
Bidirectional intercellular signaling is an essential feature of multicellular organisms, and the engineering of complex biological systems will require multiple pathways for intercellular signaling with minimal crosstalk. Natural quorum-sensing systems provide components for cell communication, but their use is often constrained by signal crosstalk. We have established new orthogonal systems for cell-cell communication using acyl homoserine lactone signaling systems. Quantitative measurements in contexts of differing receiver protein expression allowed us to separate different types of crosstalk between 3-oxo-C6- and 3-oxo-C12-homoserine lactones, cognate receiver proteins, and DNA promoters. Mutating promoter sequences minimized interactions with heterologous receiver proteins. We used experimental data to parameterize a computational model for signal crosstalk and to estimate the effect of receiver protein levels on signal crosstalk. We used this model to predict optimal expression levels for receiver proteins, to create an effective two-channel cell communication device. Establishment of a novel spatial assay allowed measurement of interactions between geometrically constrained cell populations via these diffusible signals. We built relay devices capable of long-range signal propagation mediated by cycles of signal induction, communication and response by discrete cell populations. This work demonstrates the ability to systematically reduce crosstalk within intercellular signaling systems and to use these systems to engineer complex spatiotemporal patterning in cell populations.
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Abstract
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Accurate
characterization of promoter behavior is essential for
the rational design of functional synthetic transcription networks
such as logic gates and oscillators. However, transcription rates
observed from promoters can vary significantly depending on the growth
rate of host cells and the experimental and genetic contexts of the
measurement. Furthermore, in vivo measurement methods
must accommodate variation in translation, protein folding, and maturation
rates of reporter proteins, as well as metabolic load. The external
factors affecting transcription activity may be considered to be extrinsic,
and the goal of characterization should be to obtain quantitative
measures of the intrinsic characteristics of promoters. We have developed
a promoter characterization method that is based on a mathematical
model for cell growth and reporter gene expression and exploits multiple in vivo measurements to compensate for variation due to
extrinsic factors. First, we used optical density and fluorescent
reporter gene measurements to account for the effect of differing
cell growth rates. Second, we compared the output of reporter genes
to that of a control promoter using concurrent dual-channel fluorescence
measurements. This allowed us to derive a quantitative promoter characteristic
(ρ) that provides a robust measure of the intrinsic properties
of a promoter, relative to the control. We imposed different extrinsic
factors on growing cells, altering carbon source and adding bacteriostatic
agents, and demonstrated that the use of ρ values reduced the
fraction of variance due to extrinsic factors from 78% to less than
4%. This is a simple and reliable method to quantitatively describe
promoter properties.
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12
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Age estimation in children by measurement of open apices in teeth with Bayesian calibration approach. Forensic Sci Int 2016; 258:50-4. [DOI: 10.1016/j.forsciint.2015.11.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 08/03/2015] [Accepted: 11/12/2015] [Indexed: 10/22/2022]
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13
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Pleurotus ostreatus
biofilm-forming ability and ultrastructure are significantly influenced by growth medium and support type. J Appl Microbiol 2013; 114:1750-62. [DOI: 10.1111/jam.12170] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 01/21/2013] [Accepted: 02/10/2013] [Indexed: 11/29/2022]
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14
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[Meta analysis indices of genotoxic damage in urban pollution exposed workers]. GIORNALE ITALIANO DI MEDICINA DEL LAVORO ED ERGONOMIA 2012; 34:740-743. [PMID: 23405766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
OBJECTIVES The aim of this study is to examine if urban pollution can modify indices of genotoxic damage. METHODS Research of articles inherent in the evaluation of these alterations. Differents categories of exposed workers are included in the study (cases, in number of 7287) and compaired with no exposed workers (controls, in number of 8054). To calculate the result of meta-analysis the Effect Size (ES) was used and the confidence interval was calculated. RESULTS In this category we evaluated 54 studies and we observed significantly differences in the complex. CONCLUSIONS Starting from the individual variables analysis investigated, between exposed and not exposed group, we underline the utility to deepen the studies concerning of these parameters, to appreciate their benefits and to safeguard health of exposed workers.
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A molecular framework for the inhibition of Arabidopsis root growth in response to boron toxicity. PLANT, CELL & ENVIRONMENT 2012; 35:719-34. [PMID: 21988710 DOI: 10.1111/j.1365-3040.2011.02446.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Boron is an essential micronutrient for plants and is taken up in the form of boric acid (BA). Despite this, a high BA concentration is toxic for the plants, inhibiting root growth and is thus a significant problem in semi-arid areas in the world. In this work, we report the molecular basis for the inhibition of root growth caused by boron. We show that application of BA reduces the size of root meristems, correlating with the inhibition of root growth. The decrease in meristem size is caused by a reduction of cell division. Mitotic cell number significantly decreases and the expression level of key core cell cycle regulators is modulated. The modulation of the cell cycle does not appear to act through cytokinin and auxin signalling. A global expression analysis reveals that boron toxicity induces the expression of genes related with abscisic acid (ABA) signalling, ABA response and cell wall modifications, and represses genes that code for water transporters. These results suggest that boron toxicity produces a reduction of water and BA uptake, triggering a hydric stress response that produces root growth inhibition.
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Upgrading and detoxification of aqueous extracts from dry olive mill residues by white-rot fungi. J Biotechnol 2010. [DOI: 10.1016/j.jbiotec.2010.09.059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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17
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[Protection of working woman's health]. GIORNALE ITALIANO DI MEDICINA DEL LAVORO ED ERGONOMIA 2010; 32:458-460. [PMID: 21086704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
INTRODUCTION In the past the role of women was mainly that of wife and mother, over the centuries, this role has changed: women assert themselves in every social field and workplace. OBJECTIVES Analyze the history of women's work, from prehistory to the present day highlighting the evolution of women's role over the centuries. Identify which may be the different occupational stressors, in particular the organizational and psycho-social ones, to which is submitted a working woman. MATERIALS AND METHODS The authors have analyzed the most relevant data from literature, in particular on the issue of mental health. RESULTS Provide the main forms of prevention that have to be implemented. DISCUSSION The main challenge for women today, is to balance work outside the home and housework. This added to job stressors, may interfere with the psychological and physical wellbeing of the worker.
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Improved method for isolation of bacterial inhibitors from oleuropein hydrolysis. Appl Environ Microbiol 2010; 46:509-10. [PMID: 16346374 PMCID: PMC239433 DOI: 10.1128/aem.46.2.509-510.1983] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A new high-pressure liquid chromatography multidetection quantitative method for the isolation of the products of oleuropein hydrolysis is described. A single analysis yields sufficient amounts of the compounds to test their inhibitory effect on bacterial growth.
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Assessment of olive-mill wastewater as a growth medium for lipase production by Candida cylindracea in bench-top reactor. BIORESOURCE TECHNOLOGY 2009; 100:3395-3402. [PMID: 19303284 DOI: 10.1016/j.biortech.2009.02.022] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2008] [Revised: 02/11/2009] [Accepted: 02/13/2009] [Indexed: 05/27/2023]
Abstract
Olive-mill wastewater (OMW) was investigated for its suitability to serve as a medium for lipase production by Candida cylindracea NRRL Y-17506. The OMW that best supported enzyme production was characterized by low COD and low total sugars content. In shake flask batch cultures, OMW supplementation with 2.4 g l(-1) NH(4)Cl and 3 g l(-1) olive oil led to an enzyme activity of about 10 U ml(-1). The addition of glucose or malt extract and supplements containing organic N (e.g., peptone, yeast extract) either depressed or did not affect the enzyme production. Further experiments were then performed in a 3-l stirred tank reactor to assess the impact of medium pH and stirring speed on the yeast enzyme activity. The lipase activity was low (1.8 U ml(-1)) when the pH was held constant at 6.5, significantly increased (18.7 U ml(-1)) with uncontrolled pH and was maximum (20.4 U ml(-1)) when the pH was let free to vary below 6.5. A stirring regime, that varied depending on the dissolved oxygen concentration in the medium, both prevented the occurrence of anoxic conditions during the exponential growth phase and enabled good lipase production (i.e., 21.6 U ml(-1)) and mean volumetric productivity (i.e., 123.5 Ul(-1)h(-1)).
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Oxalate consumption by lactobacilli: evaluation of oxalyl-CoA decarboxylase and formyl-CoA transferase activity in Lactobacillus acidophilus. J Appl Microbiol 2007; 103:1600-9. [DOI: 10.1111/j.1365-2672.2007.03388.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Role of autochthonous filamentous fungi in bioremediation of a soil historically contaminated with aromatic hydrocarbons. Appl Environ Microbiol 2006; 72:28-36. [PMID: 16391021 PMCID: PMC1352206 DOI: 10.1128/aem.72.1.28-36.2006] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nine fungal strains isolated from an aged and heavily contaminated soil were identified and screened to assess their degradative potential. Among them, Allescheriella sp. strain DABAC 1, Stachybotrys sp. strain DABAC 3, and Phlebia sp. strain DABAC 9 were selected for remediation trials on the basis of Poly R-478 decolorization associated with lignin-modifying enzyme (LME) production. These autochthonous fungi were tested for the abilities to grow under nonsterile conditions and to degrade various aromatic hydrocarbons in the same contaminated soil. After 30 days, fungal colonization was clearly visible and was confirmed by ergosterol determination. In spite of subalkaline pH conditions and the presence of heavy metals, the autochthonous fungi produced laccase and Mn and lignin peroxidases. No LME activities were detected in control microcosms. All of the isolates led to a marked removal of naphthalene, dichloroaniline isomers, o-hydroxybiphenyl, and 1,1'-binaphthalene. Stachybotrys sp. strain DABAC 3 was the most effective isolate due to its ability to partially deplete the predominant contaminants 9,10-anthracenedione and 7H-benz[DE]anthracen-7-one. A release of chloride ions was observed in soil treated with either Allescheriella sp. strain DABAC 1 or Stachybotrys sp. strain DABAC 3, suggesting the occurrence of oxidative dehalogenation. The autochthonous fungi led to a significant decrease in soil toxicity, as assessed by both the Lepidium sativum L. germination test and the Collembola mortality test.
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Adsorption/release behaviour of oligonucleotides on polymeric core-shell microspheres. J Control Release 2005; 101:355-6. [PMID: 15765571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
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Identification method based on PCR combined with automated ribotyping for tracking probiotic Lactobacillus strains colonizing the human gut and vagina. J Appl Microbiol 2004; 96:777-86. [PMID: 15012816 DOI: 10.1111/j.1365-2672.2004.02228.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS A molecular methodology based on PCR-associated automated ribotyping was developed to specifically detect the Lactobacillus strains of two probiotic products (an orally administered lyophilized preparation and vaginal tablets) in human faeces and vaginal swabs. METHODS AND RESULTS The 16S-23S rDNA sequences and the ribotype profiles of the probiotic lactobacilli were characterized and new species-specific primer sets were designed. The identification of faecal and vaginal lactobacilli isolated from subjects administered with the probiotic products was performed by using PCR with species-specific primers followed by strain-specific automated ribotyping. CONCLUSIONS The PCR-ribotyping identification allowed to study the colonization patterns of the probiotic lactobacilli in the human gut and vagina evidencing the strains with the best survival capability. SIGNIFICANCE AND IMPACT OF THE STUDY The proposed molecular method represents a powerful tool of strain-specific identification, useful for differentiating exogenous from indigenous strains in any microbial ecosystem and for rationally choosing probiotic bacteria with the best chance of survival in the host.
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Abstract
AIMS Isolation and characterization of the glucose oxidase (GOX)-encoding gene from a Penicillium variabile strain (P16) having a high level of GOX activity and comparison of its expression with that of another strain of P. variabile (NRRL 1048) characterized by low GOX activity. METHODS AND RESULTS The gene, isolated by PCR consisted of 1818 bp encoding 605 amino acid residues. Gene expression was analysed by Northern blotting and compared with that of P. variabile NRRL 1048. The higher GOX activity of strain P16 appeared likely because of de novo mRNA synthesis. Southern blotting analyses of the genomic DNA showed that the hybridization pattern of the two strains differed for the size of hybridizing fragment detected by the probe and slightly for their signal intensity. CONCLUSIONS The GOX-encoding gene of P. variabile P16 was isolated and characterized to identify the molecular bases of its high level of expression and in view of improving enzyme production by developing a process based on heterologous expression. SIGNIFICANCE AND IMPACT OF THE STUDY GOX-encoding genes can be subjected to high difference in their expression levels. The P16 strain of P. variable producing large amount of GOX as well as its encoding gene might be exploited for industrial applications.
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MESH Headings
- Amino Acid Sequence
- Blotting, Northern
- Blotting, Southern
- Chromosomes, Fungal/genetics
- Cloning, Molecular
- DNA, Fungal/chemistry
- DNA, Fungal/isolation & purification
- Gene Expression
- Genes, Fungal
- Genome, Fungal
- Glucose Oxidase/biosynthesis
- Glucose Oxidase/genetics
- Glucose Oxidase/metabolism
- Molecular Sequence Data
- Penicillium/enzymology
- Penicillium/genetics
- Polymorphism, Genetic
- RNA, Messenger/analysis
- Sequence Alignment
- Sequence Analysis, DNA
- Time Factors
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Abstract
Botryosphaeria rhodina produced beta-glucan when grown on undiluted olive-mill wastewaters (OMW). The production of exopolysaccharide increased with the COD up to 17.2 g l(-1) on the most loaded OMW (151 and 66 g l(-1) of COD and total sugar, respectively). The total phenol content of OMW was reduced from 8 to 4.1 g l(-1).
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Immobilized cell technology applied in solubilization of insoluble inorganic (rock) phosphates and P plant acquisition. BIORESOURCE TECHNOLOGY 2001; 79:263-271. [PMID: 11499580 DOI: 10.1016/s0960-8524(01)00017-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This paper reviews current knowledge of the production of organic acids by immobilized microorganisms with a simultaneous solubilization of rock phosphate in fermentation and soil conditions. The most widely applied methods are based on the passive immobilization in preformed porous carriers and entrapment of the microbial cells in natural gels. In general, immobilized systems show higher acid producing and rock phosphate solubilizing activity than freely suspended cells. The potential of gel-entrapped P-solubilizers and mycorrhizal fungi as microbial soil inoculants is also pointed out. Some advantages and constraints of using immobilized cells are discussed and a special emphasis on further research is given.
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The chitinolytic activity of Penicillium janthinellum P9: purification, partial characterization and potential applications. J Appl Microbiol 2001; 91:498-505. [PMID: 11556916 DOI: 10.1046/j.1365-2672.2001.01409.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS To purify and characterize the chitinolytic activity of Penicillium janthinellum P9 and to evaluate possible uses of the purified enzymes in the control of fungal growth and spore germination. METHODS AND RESULTS The chitinolytic activity of P. janthinellum P9 was associated to two beta-N-acetyl-hexosaminidases (CHI1 and CHI2) that were purified by preparative isoelectric focusing and preparative electrophoresis and partially characterized. Treatment of test fungi with purified enzyme solutions caused reduced spore germination, reduction of hyphal length and mycelial damage. The combined action of the two enzymes and a systemic fungicide completely inactivated pests and food-spoiling moulds such as Fusarium solanii, P. canescens and Cladosporium cladosporioides. Treatment with the two enzymes increased germination of freeze-dried fungal spores. CONCLUSION The chitinolytic activity of P. janthinellum P9 is associated with two extracellular beta-N-acetyl-hexosaminidases that can cause damage to the cell walls of other fungi. SIGNIFICANCE AND IMPACT OF THE STUDY This appears to be the first report on the characterization of extracellular chitinolytic enzymes produced by a Penicillium strain. The results of this study might have some impact in the applied research field.
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Two-photon microscopy and spectroscopy based on a compact confocal scanning head. JOURNAL OF BIOMEDICAL OPTICS 2001; 6:300-310. [PMID: 11516320 DOI: 10.1117/1.1382809] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2001] [Revised: 03/24/2001] [Accepted: 04/11/2001] [Indexed: 05/23/2023]
Abstract
We have combined a confocal laser scanning head modified for TPE (two-photon excitation) microscopy with some spectroscopic modules to study single molecules and molecular aggregates. The behavior of the TPE microscope unit has been characterized by means of point spread function measurements and of the demonstration of its micropatterning abilities. One-photon and two-photon mode can be simply accomplished by switching from a mono-mode optical fiber (one-photon) coupled to conventional laser sources to an optical module that allows IR laser beam (two-photon/TPE) delivery to the confocal laser scanning head. We have then described the characterization of the two-photon microscope for spectroscopic applications: fluorescence correlation, lifetime and fluorescence polarization anisotropy measurements. We describe the measurement of the response of the two-photon microscope to the light polarization and discuss fluorescence polarization anisotropy measurements on Rhodamine 6G as a function of the viscosity and on a globular protein, the Beta-lactoglobulin B labeled with Alexa 532 at very high dilutions. The average rotational and translational diffusion coefficients measured with fluorescence polarization anisotropy and fluorescence correlation methods are in good agreement with the protein size, therefore validating the use of the microscope for two-photon spectroscopy on biomolecules.
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Abstract
The production of itaconic acid from glucose-based media by Aspergillus terreus NRRL 1960 was found to be controlled by stirring rate and pH. When the phosphorous (P) level in the production medium was reduced to less than 10 mg l(-1), the fungal mycelium exhausted its primary growth and started to excrete itaconic acid, while it continued its secondary growth at the expense of ammoniacal nitrogen. The fermentation exhibited a mixed-growth-associated product formation kinetics, the non-growth associated production term (mI) being practically zero only when the pH was left free to change from 3.4 down to 1.85. On the contrary, when the pH was kept reducing up to a constant value by automatic addition of KOH 4 mol l(-1), the itaconate yield coefficient on the initial glucose supplied (Y(I/So)) and mI and were 0.53 g g(-1) and 0.028 h(-1) at pH 2.4 and 320 rev min(-1) and 0.5 g g(-1) and 0.036 h(-1) at pH 2.8 and 400 rev min(-1), respectively. Although the differences between mI and Y(I/So) were statistically insignificant at the 95% confidence level, the net difference in the corresponding yield coefficients for itaconic acid on mycelial biomass resulted in a maximum itaconate production rate of 0.41 g l(-1) h(-1) at pH 2.8 and 400 rev min(-1), thus showing that this operating condition is no doubt optimal for the process under study.
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Abstract
Extracellular pigment production by immobilised Monascus purpureus C322 has been studied in repeated-batch processes using different immobilising carriers such as Ca-alginate, polyurethane sponge, active carbon and pearlite. With Ca-alginate, pigment production was maximum (30.5 UA470 as process mean production, three batches) while the cell leakage was negligible (0.4 g 1(-1) free biomass) and the bead mechanical stability good; with this carrier, an extended repeated-batch fermentation (nine batches, 55 days) was carried out: the process pigment productivity was 3.87 UA470 day(-1).
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Synthesis, X-ray powder structure, and magnetic properties of the new, weak ferromagnet iron(II) phenylphosphonate. Inorg Chem 2000; 39:1803-8. [PMID: 12526572 DOI: 10.1021/ic9914995] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
A new molecule-based weak ferromagnet of formula Fe[C6H5PO3].H2O was synthesized. It was characterized by thermogravimetric analysis and UV-visible and infrared spectroscopy, and the magnetic properties were studied using a superconducting quantum interference device magnetometer. The crystal structure of the compound was determined "ab initio" from X-ray powder diffraction data and refined by the Rietveld method. The crystals of Fe[C6H5PO3].H2O are orthorhombic, space group Pmn2(1), with a = 5.668(8) A, b = 14.453(2) A, c = 4.893(7) A, and Z = 2. The title compound is isostructural with the previously reported lamellar M[C6H5PO3].H2O, M = Mn(II), Zn(II), and Cd(II). The inorganic layers are made of Fe(II) ions octahedrally coordinated by five phosphonate oxygen atoms and one from oxygen of the water molecule. These layers are then separated by bilayers of the phenyl groups, and van der Waals contacts are established between them. The refinement has shown that the phenyl rings are disordered in the lattice. The oxidation state of the metal ion is +2, and the electronic configuration is d6 (S = 2) high-spin, as determined from dc magnetic susceptibility measurements from 150 K to room temperature. Below 100 K, the magnetic moment of Fe[C6H5PO3].H2O rises rapidly to a maximum at TN = 21.5 K, and then it decreases again. The peak at TN is associated with the 3D antiferromagnetic long-range ordering. Below the critical temperature, the title compound behaves as a "weak" ferromagnet, which represents the third type of magnetic materials characterized by having a finite zero-field magnetization, ferromagnets and ferrimagnets being the other two types. The large coercive field (i.e., 6400 G) observed in the hysteresis loop at T = 10 K is rare in molecule-based materials; it can be ascribed to a pronounced spin-orbit coupling for the 5T2g ground state of the Fe(II) ion in the octahedral environment.
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39
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High-rate aerobic treatment of winery wastewater using bioreactors with free and immobilized activated sludge. J Biosci Bioeng 2000; 90:381-6. [PMID: 16232876 DOI: 10.1016/s1389-1723(01)80005-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2000] [Accepted: 06/26/2000] [Indexed: 10/26/2022]
Abstract
COD (chemical oxygen demand) removal rate and efficiency of winery wastewater (WW) aerobic treatments were evaluated in an air-bubble column bioreactor using self-adapted microbial populations either free or immobilized on polyurethane particles and in a packed-bed bioreactor immobilized on Raschig rings. The bioreactors were fed continuously for up to 12 months using WW of different origins and with different pollution loads (COD range, 0.8-11.0 kg.m(-3)): the maximum loading rate was approx. 8.8 kg-COD m(-3).d(-1). The highest COD removal rate (6.6 kg.m(-3).d(-1)) was obtained with free activated sludge in the bubble column bioreactor; treatment efficiency and hydraulic retention time were >90% and approx. 0.8 d, respectively. The microbial populations in the three reactors were characterized.
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Inactivation of Mucor plumbeus by the combined actions of chitinase and high hydrostatic pressure. Int J Food Microbiol 1999; 52:109-13. [PMID: 10573398 DOI: 10.1016/s0168-1605(99)00114-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Sporangiospores were treated with high hydrostatic pressure and/or fungal chitinase in order to study the inhibition of germination and growth of the food spoiling mold Mucor plumbeus. Total fungal inhibition was obtained either at 4.0 kbar or by 10 U/ml of chitinase from Penicillium janthinellum. A pretreatment with 1 U/ml of the same chitinase reduced the pressure necessary to obtain complete spore inhibition to 3 kbar.
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Production and properties of the linamarase and amygdalase activities of Penicillium aurantiogriseum P35. Biosci Biotechnol Biochem 1999; 63:805-12. [PMID: 10380623 DOI: 10.1271/bbb.63.805] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The effects of medium composition on the production of beta-glucosidase (amygdalase and linamarase) by Penicillium aurantiogriseum P35 were studied and the medium optimized as follows (g/l of deionized water): pectin, 10.0; (NH4)2SO4, 8.0; KH2PO4, 8.0; Na2HPO4, 2.8; MgSO4.7H2O, 0.5; yeast extract, 4.0; initial pH 6.0. When grown in a bench fermenter on this medium, the fungus produced 50.5 mU of amygdalase and 9.4 mU of linamarase per ml of culture broth. Two beta-glucosidases (PGI and PGII), each having amygdalase and linamarase activities, were recovered from the culture broth and purified; their relative molecular weights, as native enzymes, were estimated to be about 247,000 and 147,000, respectively. Both enzymes showed the same optimum pH (6.0) but different optimum temperatures (55 and 60 degrees C for PGI and PGII, respectively). Thermostability (10 min at 60 degrees C) and half-life of enzyme activity (7 hours at 60 degrees C) of PGII were higher than those of PGI (10 min at 50 degrees C and 2 hours at 55 degrees C, respectively). A wide range of cyanogenic glycosides (such as tetraphyllin B, epivolkenin, gynocardin, passibiflorin, prunasin, taxiphyllin, amygdalin, lucumin, sambunigrin, dhurrin, linamarin and cardiospermin sulfate) were hydrolyzed by both enzymes.
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Abstract
The chitinolytic activity of Verticillium cfr. lecanii A3, a strain isolated from continental Antarctica, was compared to those of two selected strains of Trichoderma harzianum. After 72 h of incubation at 25 degrees C in media containing chitin as the sole carbon source, all strains showed the same enzyme activity (ca. 230 mU/ml); at 15 degrees C, the levels of enzyme activity of the three strains were similar to those obtained at 25 degrees C. At 5 degrees C, in contrast, the activity of V. lecanii was ca. 4 times higher than those of both strains of T. harzianum (203 and 57 mU/ml, respectively; incubation time 144 h). The chitinase of V. lecanii, purified by preparative isoelectric focusing and ion-exchange chromatography, was shown to be a glycoprotein with apparent molecular weight of 45 kDa and isoelectric point of 4.9. The enzyme was active over a broad range of temperatures (5-60 degrees C): at 5 degrees C, its relative activity was still 50% of that recorded at 40 degrees C (optimal temperature). V. lecanii and its purified chitinase showed clear inhibitory effects on the growth of some test moulds such as Mucor plumbeus, Cladosporium cladosporioides, Aspergillus versicolor and Penicillium verrucosum: observations under the light and scanning electron microscopes revealed that growth inhibition was accompanied by mycelial damage and cell lysis.
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Amygdalin degradation by Mucor circinelloides and Penicillium aurantiogriseum: mechanisms of hydrolysis. Arch Microbiol 1998; 169:106-12. [PMID: 9446681 DOI: 10.1007/s002030050549] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Mucor circinelloides LU M40 and Penicillium aurantiogriseum P 35 produce extracellular beta-glycosidases that are active on the cyanogenic glycoside amygdalin. From the culture broths of M. circinelloides, only one beta-glycosidase could be identified, while two different enzymes - both having amygdalase activity - were found in culture broths of P. aurantiogriseum. The study of the mechanism of hydrolysis of the beta-bis-glycoside amygdalin with purified enzymes from the two organisms indicated a possible sequential (two-step) reaction. In all cases, the first step of hydrolysis from amygdalin to prunasin was very rapid, while the second step from prunasin to cyanohydrin was much slower. No cyanohydrin lyase activity was found in the culture broths of either fungus.
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Abstract
Enantioseparation of 2-arylpropionic acids (Flobufen) and dansyl-derivatives of amino acids can be achieved in 10-15 min by electrochromatography using a capillary coated with poly-terguride. It was found that the analytes, in the range of the buffer pH between 2.5-4.0, were driven by anodic electroosmotic flow originated by the positively charged moieties of the ergolinic skeleton, and, only partially, by their anodic electrophoretic mobility. The enantiomers eluted with the same sequence, e.g. L- or (S)-isomer more retained than D- or (R)-, which was observed in HPLC separations on terguride-silica based CSPs, thus indicating that racemates were resolved by a similar chiral recognition mechanism. The retention of the solutes was affected by the concentration and composition of the effluent. An other mobile phase variable, strongly affecting the selectivity, was the pH of the buffer.
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Glucose oxidase and catalase activities ofPenicillium variabile P16 immobilized in polyurethane sponge. ACTA ACUST UNITED AC 1996. [DOI: 10.1007/bf01570142] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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46
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47
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Two-step hydrolysis of amygdalin in molds. RIVISTA DI BIOLOGIA 1996; 89:493-6. [PMID: 9122587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Mucor circinelloides LU M40 and Penicillium aurantiogriseum P 35, characterized by extracellular beta-glucosidase activity on cyanogenic glycosides, hydrolyse amygdalin by a two-step reaction mechanism being the first step of hydrolysis, from amygdalin to prunasin, very rapid (15 min) and the second one, from prunasin to mandelonitrile, much slower (120 min).
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New Organic Monosized Microspheres for Use in Enantiomer Separations by High-Performance Liquid Chromatography. ACTA ACUST UNITED AC 1995. [DOI: 10.1080/10826079508010444] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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49
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Glucose oxidase, catalase and gluconic acid production by immobilized mycelium of Penicillum variabile P16. Biotechnol Lett 1994. [DOI: 10.1007/bf00128629] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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50
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Day Hospital and resources utilization: A DRG-analysis of the relationship between costs and benefits. Urologia 1994. [DOI: 10.1177/039156039406100203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
We present the results of our analysis on the operative efficiency of the Day Hospital since it opened on 27/04/92 in the Division of Urology of ULSS 4 Parma. This study has been performed by comparing both median stays in hospital for the numerically more representative surgical operations (prostatectomy, TURP, TURV) and by using the DRG system. The DRG specific cost for every hospitalization has also been calculated. Both systems show an increase in the number of treated cases and a decrease in the average hospitalization. This positive trend has been confirmed by the analysis of the costs.
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