Recent findings in methanotrophs: genetics, molecular ecology, and biopotential

The potential consequences for mankind could be disastrous due to global warming, which arises from an increase in the average temperature on Earth. The elevation in temperature primarily stems from the escalation in the concentration of greenhouse gases (GHG) such as CO2, CH4, and N2O within the atmosphere. Among these gases, methane (CH4) is particularly significant in driving alterations to the worldwide climate. Methanotrophic bacteria possess the distinctive ability to employ methane as both as source of carbon and energy. These bacteria show great potential as exceptional biocatalysts in advancing C1 bioconversion technology. The present review describes recent findings in methanotrophs including aerobic and anaerobic methanotroph bacteria, phenotypic characteristics, biotechnological potential, their physiology, ecology, and native multi-carbon utilizing pathways, and their molecular biology. The existing understanding of methanogenesis and methanotrophy in soil, as well as anaerobic methane oxidation and methanotrophy in temperate and extreme environments, is also covered in this discussion. New types of methanogens and communities of methanotrophic bacteria have been identified from various ecosystems and thoroughly examined for a range of biotechnological uses. Grasping the processes of methanogenesis and methanotrophy holds significant importance in the development of innovative agricultural techniques and industrial procedures that contribute to a more favorable equilibrium of GHG. This current review centers on the diversity of emerging methanogen and methanotroph species and their effects on the environment. By amalgamating advanced genetic analysis with ecological insights, this study pioneers a holistic approach to unraveling the biopotential of methanotrophs, offering unprecedented avenues for biotechnological applications. KEY POINTS: • The physiology of methanotrophic bacteria is fundamentally determined. • Native multi-carbon utilizing pathways in methanotrophic bacteria are summarized. • The genes responsible for encoding methane monooxygenase are discussed.

Fabrication and characterization of talipot starch-based biocomposite film using mucilages from different plant sources: A comparative study

Biocomposite films were prepared by formulating talipot starch with plant mucilage derived from shoeblack leaves, okra, and seeds of basil, fenugreek, and flax, which were identified as SBM-TSF, OKM-TSF, BSM-TSF, FGM-TSF, and FXM-TSF, respectively. The plant mucilages enhanced the crosslinking of the filmogenic solutions, which increased the film's relative crystallinity. Upon topographical investigation, the biocomposite films exhibited the same compact and homogeneous structures as the native talipot starch film (NTSF), but with finer corrugations. When compared to NTSF, the addition of plant mucilage decreased the moisture content while increasing the thickness and opacity. SBM-TSF showed significantly reduced (p ≤ 0.05) solubility and water vapor permeability, indicating that increased crosslink formation in the film obstructed the water vapor passage. Among all the biocomposite films, the BSM-TSF had the greatest tensile strength, making it more resistant to stretching. Among the studied biocomposite films, SBM-TSF and BSM-TSF demonstrated improved thermal and biodegradation stability.

An investigation of slaughter weight and muscle type effects on carcass fatty acid profiles and meat textural characteristics of young Holstein Friesian bulls

Study objectives included the assessment of carcass fatty acid composition and meat texture characteristics of younger Holstein Friesian bulls. Three experimental groups were formed based on the weights of the 23 young bulls at slaughter: lighter, medium, and heavier. Samples were taken from the Gluteus medius (GM) and Longissimus thoracis muscles 24 h after slaughter. Fatty acid composition, Warner-Bratzler Meat Shear (WBS) measurements, as well as textural profile analysis (TPA) and sensory analysis of the muscle samples were conducted. The fatty acid composition was determined using Thin Layer Chromatography (HPTLC). Polyunsaturated fatty acids and dietary fatty acids give a neutral hypocholesterolemic effect in direct fluorescent antibody (DFA) contents, DFA/OFA (C14:0+C16:0) ratio, hardness, Warner-Bratzler Shear force and also the chews number - which is desirable - before swallowing (NCBS) the meat were significantly decreased with the increasing slaughter weight. Higher slaughter weight resulted in a larger amount of beef with a better panel tenderness score; however, the meat obtained from the LSW group was less healthy considering the fatty acid profile. Additionally, internal fat contained the highest saturated fatty acids concentrations, while subcutaneous fat contained the highest amount of monounsaturated fatty acids. Furthermore, intramuscular fat levels were highest in PUFA and PUFA/SFA ratio. As a result, this study strongly suggests that slaughter weight and anatomical location of fat samples contribute significantly to meat texture characteristics and fatty acid profiles in Holstein Friesian bulls.

Laccase-mediated degradation of petroleum hydrocarbons in historically contaminated soil

Laccases (EC1.10.3.2) have attracted growing attention in bioremediation research due to their high reactivity and substrate versatility. In this study, three genes for potential novel laccases were identified in an enrichment culture from contaminated field soil and recombinantly expressed in E. coli. Two of them, designated as PlL and BaL, were biochemically characterized regarding their optimal pH and temperature, kinetic parameters, and substrate versatility. In addition, lacasse PlL from Parvibaculum lavamentivorans was tested on historically contaminated soil. Treatment with PlL led to a significantly higher reduction of total petroleum hydrocarbons (83% w/w) compared to the microbial control (74% w/w). Hereby, PlL was especially effective in degrading hydrocarbons > C17. Their residual concentration was by 43% w/w lower than in the microbial treatment. In comparison to the laccase from Myceliophthora thermophila (MtL), PlL treatment was not significantly different for the fraction > C17 but resulted in a 30% (w/w) lower residual concentration for hydrocarbons < C18. In general, PlL can promote the degradation of petroleum hydrocarbons. As a consequence, it can be applied to reduce remediation time by duly achieving remediation target concentrations needed for site closure.

What Are "Bioplastics"? Defining Renewability, Biosynthesis, Biodegradability, and Biocompatibility

Today, plastic materials are mostly made from fossil resources, and they are characterized by their long lifetime and pronounced persistence in the open environment. These attributes of plastics are one cause of the ubiquitous pollution we see in our environment. When plastics end up in the environment, most of this pollution can be attributed to a lack of infrastructure for appropriately collecting and recycling plastic waste, mainly due to mismanagement. Because of the huge production volumes of plastics, their merits of being cheap to produce and process and their recalcitrance have turned into a huge disadvantage, since plastic waste has become the end point of our linear economic usage model, and massive amounts have started to accumulate in the environment, leading to microplastics pollution and other detrimental effects. A possible solution to this is offered by "bioplastics", which are materials that are either (partly) biobased and/or degradable under defined conditions. With the rise of bioplastics in the marketplace, several standards and test protocols have been developed to assess, certify, and advertise their properties in this respect. This article summarizes and critically discusses different views on bioplastics, mainly related to the properties of biodegradability and biobased carbon content; this shall allow us to find a common ground for clearly addressing and categorizing bioplastic materials, which could become an essential building block in a circular economy. Today, bioplastics account for only 1-2% of all plastics, while technically, they could replace up to 90% of all fossil-based plastics, particularly in short-lived goods and packaging, the single most important area of use for conventional plastics. Their replacement potential not only applies to thermoplastics but also to thermosets and elastomers. Bioplastics can be recycled through different means, and they can be made from renewable sources, with (bio)degradability being an option for the mismanaged fraction and special applications with an intended end of life in nature (such as in seed coatings and bite protection for trees). Bioplastics can be used in composites and differ in their properties, similarly to conventional plastics. Clear definitions for "biobased" and "biodegradable" are needed to allow stakeholders of (bio)plastics to make fact-based decisions regarding material selection, application, and end-of-life options; the same level of clarity is needed for terms like "renewable carbon" and "bio-attributed" carbon, definitions of which are summarized and discussed in this paper.

Characterization of Poly(3-hydroxybutyrate) (P3HB) from Alternative, Scalable (Waste) Feedstocks

Bioplastics hold significant promise in replacing conventional plastic materials, linked to various serious issues such as fossil resource consumption, microplastic formation, non-degradability, and limited end-of-life options. Among bioplastics, polyhydroxyalkanoates (PHA) emerge as an intriguing class, with poly(3-hydroxybutyrate) (P3HB) being the most utilized. The extensive application of P3HB encounters a challenge due to its high production costs, prompting the investigation of sustainable alternatives, including the utilization of waste and new production routes involving CO2 and CH4. This study provides a valuable comparison of two P3HBs synthesized through distinct routes: one via cyanobacteria (Synechocystis sp. PCC 6714) for photoautotrophic production and the other via methanotrophic bacteria (Methylocystis sp. GB 25) for chemoautotrophic growth. This research evaluates the thermal and mechanical properties, including the aging effect over 21 days, demonstrating that both P3HBs are comparable, exhibiting physical properties similar to standard P3HBs. The results highlight the promising potential of P3HBs obtained through alternative routes as biomaterials, thereby contributing to the transition toward more sustainable alternatives to fossil polymers.

Infrared Thermography Assessment of Aerobic Stability of a Total Mixed Ration: An Innovative Approach to Evaluating Dairy Cow Feed

A major objective of this study is to identify factors influencing the quality of high-moisture total mixed rations (TMRs) for livestock feed and explore possible manipulations that can enhance their fermentation characteristics and stability in order to address the problem of poor aerobic stability. Therefore, the current study utilized infrared thermography (IRT) to assess the aerobic stability of water-added TMRs in the feed bunker. By manipulating the moisture content of freshly prepared TMRs at four different levels through water addition and subjecting it to storage at two consistent temperatures, significant correlations between IRT values (center temperature (CT) and maximum temperature difference (MTD)) and key parameters such as lactic acid bacteria, water-soluble carbohydrates, and TMR pH were established. The first and second principal components together accounted for 44.3% of the variation, with the first component's load influenced by IRT parameters, fermentation characteristics, and air exposure times, while the second component's load was influenced by dry matter content and lactic acid concentration. The results of these studies indicate the possibility that feeding methods can be optimized by identifying portions with higher CT or MTD data using IRT measurements just before feeding dairy cows in the field. As a result, increasing the use of IRT in feed management and preservation processes is projected to have a positive impact on animal productivity in the future.

P3HB from CH4 using methanotrophs: aspects of bioreactor, fermentation process and modelling for cost-effective biopolymer production

P3HB (poly-β-hydroxybutyrate), an energy-storage compound of several microorganisms, can be used as bioplastics material. P3HB is completely biodegradable under aerobic and aerobic conditions, also in the marine environment. The intracellular agglomeration of P3HB was examined employing a methanotrophic consortium. Supplanting fossil, non-degradable polymers by P3HB can significantly reduce the environmental impact of plastics. Utilizing inexpensive carbon sources like CH₄ (natural gas, biogas) is a fundamental methodology to make P3HB production less costly, and to avoid the use of primary agricultural products such as sugar or starch. Biomass growth in polyhydroxyalkanoates (PHA) in general and in Poly (3-hydroxybutyrate) manufacture in specific could be a foremost point, so here the authors focus on natural gas as a proper carbon source and on the selection of bioreactors to produceP3HB, and in future further PHA, from that substrate. CH₄ can also be obtained from biomass, e.g., biogas, syngas methanation or power-to-gas (synthetic natural gas, SNG). Simulation software can be utilized for examination, optimizing and scale-up of the process as shown in this paper. The fermentation systems continuously stirred tank reactor (CSTR), forced-liquid vertical loop bioreactor (VTLB), forced-liquid horizontal tubular loop bioreactor (HTLB), airlift (AL) fermenter and bubble column (BC) fermenter were compared for their methane conversion, kLa value, productivity, advantages and disadvantages. Methane is compared to methanol and other feedstocks. It was discovered that under optimum processing circumstances and using Methylocystis hirsuta, the cells accumulated 51.6% cell dry mass of P3HB in the VTLB setup.

Comparison of Black Tea Waste and Legume Roughages: Methane Mitigation and Rumen Fermentation Parameters

The chemical composition, in vitro total gas and CH₄ production and performance of cattle fed on factory black tea waste (Camellia sinensis) (BTW), alfalfa (Medicago Sativa), sainfoin (Onobrychis sativa) and white clover (Trifolium repens) was investigated. The gas production was quantified at the 24th hour of the incubation process. BTW was found to vary from roughages in chemical composition (p < 0.05). In addition, the roughages differed in terms of nutrient composition and gas production (p < 0.05). In legume roughages, acetic acid (AA), propionic acid (PA), butyric acid (BA), and total volatile fatty acids (TVFA) values ranged from 52.36-57.00 mmol/L, 13.46-17.20 mmol/L, 9.79-12.43 mmol/L, and 79.71-89.05 mmol/L, respectively. In comparison with black tea waste, legume roughages had higher values of AA, PA, BA, and TVFA. Black tea waste contained a higher acetic acid ratio than legume roughages when compared as a percentage. There was a similar ratio of propionic acid to the rate calculated for sainfoin (Onobrychis sativa) and clover (Trifolium repens), and a similar ratio of butyric acid to the ratio determined for alfalfa (Medicago Sativa). The current study shows that the 5.7-6.3% tannin content of black tea waste can be used in ruminant rations with high-quality roughages. Due to the fact that BTW reduces methane emissions from ruminants and eliminates energy waste from them, the environment can be improved. To obtain more reliable results, further animal feeding experiments on legume roughages and BTW are required.

Supplementary Feed Additives Can Improve Lamb Performance in Terms of Birth Weight, Body Size, and Survival Rate

To evaluate the effects of supplementation of feed additives in the last trimester of pregnancy on placental characteristics and offspring performance, this study was conducted with 48 estrous-synchronized Ghezel ewes that had randomly been assigned to one of the following six groups (n = 8): ad libitum feeding (AL); feed restriction (RF; 60% of ad libitum intake); feed restriction + propylene glycol (PG); feed restriction + propylene glycol + monensin sodium (MS); feed restriction + propylene glycol + rumen-protected choline chloride (RPC); feed restriction + propylene glycol + monensin sodium + rumen-protected choline chloride (PMC). Birth weight, body size, and rectal temperature of lambs were determined within 24 h of birth. The presence of lambs at 87 days of age was used as an index of survival to weaning. The outcome of this study was that the average placental weight of ewes in the AL and MS groups was the highest and lowest, respectively, among the treatment groups (p < 0.01). RPC ewes presented higher placental efficiency compared to AL, RF, and MS ewes (p < 0.05). The largest and smallest crown-to-rump lengths (CRLs) were observed in PMC and RF lambs, respectively (p < 0.01). In addition, lambs born from PMC, RPC, and PG ewes had a longer curved crown-to-rump length (CCRL) than those born from AL and RF ewes (p < 0.01). The concurrent administration of propylene glycol and rumen-protected choline chloride resulted in the highest birth weight among treatment groups (p < 0.01). Lambs born to PMC and RPC ewes had a higher survival rate and rectal temperature than those born to RF ewes (p < 0.05). It can be concluded that although dietary restriction does not have adverse effects on lambs’ performance compared with ad libitum intake, the combined administration of propylene glycol and rumen-protected choline chloride in the ewes’ restricted diet can improve placental characteristics and subsequently amend lambs’ birth weight and body size. Therefore, the combined administration of these additives can be practiced during feed restriction.

Towards an automated data cleaning with deep learning in CRESST

The CRESST experiment employs cryogenic calorimeters for the sensitive measurement of nuclear recoils induced by dark matter particles. The recorded signals need to undergo a careful cleaning process to avoid wrongly reconstructed recoil energies caused by pile-up and read-out artefacts. We frame this process as a time series classification task and propose to automate it with neural networks. With a data set of over one million labeled records from 68 detectors, recorded between 2013 and 2019 by CRESST, we test the capability of four commonly used neural network architectures to learn the data cleaning task. Our best performing model achieves a balanced accuracy of 0.932 on our test set. We show on an exemplary detector that about half of the wrongly predicted events are in fact wrongly labeled events, and a large share of the remaining ones have a context-dependent ground truth. We furthermore evaluate the recall and selectivity of our classifiers with simulated data. The results confirm that the trained classifiers are well suited for the data cleaning task.

Effects of Slaughter Age of Holstein Friesian Bulls on Meat Quality: Chemical Composition, Textural Characteristics, Sensory Attributes and Fatty Acid Profile

This study aimed to investigate the effects of slaughter age (young vs. old), muscle type (Longissimus dorsi (LD), Gluteus medius (GM)) and fat deposits (kidney knob and channel fat, subcutaneous fat, intramuscular fat) on chemical, organoleptic, textural characteristics and fatty acid composition of Holstein Friesian bull meat. For this purpose, the carcasses of 26 Holstein Friesian bulls that had been fattened on the same private farm were assigned to two experimental groups based on their age at slaughter: a young group (YG) (average age: 17.0 ± 1.0 months old) and an old group (OG) (average age: 22.0 ± 1.0 months old). The percentage of crude protein, panel tenderness score, polyunsaturated fatty acid (PUFA) and saturated fatty acid (SFA) content, the PUFA/SFA ratio and the hypocholesterolemic fatty acid (DFA)/hypercholesterolemic fatty acid (OFA) ratio of the bull carcasses decreased significantly with increasing slaughter age. By contrast, the OFA content of the carcasses significantly increased (p < 0.05) with increasing slaughter age. Advanced slaughter age resulted in lower panel tenderness scores. Additionally, the meat of the bulls in the OG was considered to be less healthy because of the less desirable fatty acid composition and nutritional indices, such as the PUFA/SFA and hypocholesterolemic/hypercholesterolemic ratios, compared to the meat from the bulls in the YG. Furthermore, the intramuscular fat and internal fat contained high percentages of PUFA and SFA and high PUFA/SFA and hypocholesterolemic/hypercholesterolemic ratios. Interestingly, the percentage of OFA content in the internal and intramuscular fat tissues decreased with increasing slaughter age. In conclusion, this study provided evidence that slaughter age and muscle and fat type are essential sources of variations in the textural characteristics, sensory panel attributes and fatty acid profile of meat from Holstein Friesian bulls.

Management of Enteric Methane Emissions in Ruminants Using Feed Additives: A Review

In ruminants' metabolism, a surplus of hydrogen is removed from the reduction reaction of NAD⁺ (nicotinamide adenine dinucleotide) by the formation of methane by methanogenic bacteria and archaea methanogens. The balance of calculations between VFA (volatile fatty acids), CO₂, and CH₄ indicates that acetate and butyrate play a role in methane production, while the formation of propionate maintains hydrogen and therefore reduces methane production. CH₄ formation in ruminant livestock is not desired because it reduces feed efficiency and contributes to global warming. Therefore, numerous strategies have been investigated to mitigate methane production in ruminants. This review focuses on feed additives which have the capability of reducing methane emissions in ruminants. Due to the environmental importance of methane emissions, such studies are needed to make milk and meat production more sustainable. Additionally, the additives which have no adverse effects on rumen microbial population and where the reduction effects are a result of their hydrogen sink property, are the best reduction methods. Methane inhibitors have shown such a property in most cases. More work is needed to bring methane-reducing agents in ruminant diets to full market maturity, so that farmers can reap feed cost savings and simultaneously achieve environmental benefits.

Methane Single Cell Protein: Potential to Secure a Global Protein Supply Against Catastrophic Food Shocks

Global catastrophes such as a supervolcanic eruption, asteroid impact, or nuclear winter could cause global agricultural collapse due to reduced sunlight reaching the Earth’s surface. The human civilization’s food production system is unprepared to respond to such events, but methane single cell protein (SCP) could be a key part of the solution. Current preparedness centers around food stockpiling, an excessively expensive solution given that an abrupt sunlight reduction scenario (ASRS) could hamper conventional agriculture for 5–10 years. Instead, it is more cost-effective to consider resilient food production techniques requiring little to no sunlight. This study analyses the potential of SCP produced from methane (natural gas and biogas) as a resilient food source for global catastrophic food shocks from ASRS. The following are quantified: global production potential of methane SCP, capital costs, material and energy requirements, ramp-up rates, and retail prices. In addition, potential bottlenecks for fast deployment are considered. While providing a more valuable, protein-rich product than its alternatives, the production capacity could be slower to ramp up. Based on 24/7 construction of facilities, 7%–11% of the global protein requirements could be fulfilled at the end of the first year. Despite significant remaining uncertainties, methane SCP shows significant potential to prevent global protein starvation during an ASRS at an affordable price—US$3–5/kg dry.

Effect of Thermal Pretreatments on Phosphorylation of Corypha umbraculifera L. Stem Pith Starch: A Comparative Study Using Dry-Heat, Heat-Moisture and Autoclave Treatments

Talipot starch, a non-conventional starch source with a high yield (76%) from the stem pith of talipot palm (Corypha umbraculifera L.) was subjected to three different thermal treatments (dry-heat, heat-moisture and autoclave treatments) prior to phosphorylation. Upon dual modification of starch with thermal treatments and phosphorylation, the phosphorous content and degree of crosslinking significantly increased (p ≤ 0.05) and was confirmed by the increased peak intensity of P=O and P-O-C stretching vibrations compared to phosphorylated talipot starch in the FT-IR spectrum. The highest degree of crosslinking (0.00418) was observed in the autoclave pretreated phosphorylated talipot starch sample. Thermal pretreatment remarkably changed the granule morphology by creating fissures and grooves. The amylose content and relative crystallinity of all phosphorylated talipot starches significantly decreased (p ≤ 0.05) due to crosslinking by the formation of phosphodiester bonds, reducing the swelling power of dual-modified starches. Among all modified starches, dry-heat pretreated phosphorylated starch gel showed an improved light transmittance value of 28.4%, indicating reduced retrogradation tendency. Pasting and rheological properties represented that the thermal pretreated phosphorylated starch formed stronger gels that improved thermal and shear resistance. Autoclave treatment before phosphorylation of talipot starch showed the highest resistant starch content of 48.08%.

Interlaboratory evaluation of Mucorales PCR assays for testing serum specimens: A study by the fungal PCR Initiative and the Modimucor study group

Interlaboratory evaluations of Mucorales qPCR assays were developed to assess the reproducibility and performance of methods currently used. The participants comprised 12 laboratories from French university hospitals (nine of them participating in the Modimucor study) and 11 laboratories participating in the Fungal PCR Initiative. For panel 1, three sera were each spiked with DNA from three different species (Rhizomucor pusillus, Lichtheimia corymbifera, Rhizopus oryzae). For panel 2, six sera with three concentrations of R. pusillus and L. corymbifera (1, 10, and 100 genomes/ml) were prepared. Each panel included a blind negative-control serum. A form was distributed with each panel to collect results and required technical information, including DNA extraction method, sample volume used, DNA elution volume, qPCR method, qPCR template input volume, qPCR total reaction volume, qPCR platform, and qPCR reagents used. For panel 1, assessing 18 different protocols, qualitative results (positive or negative) were correct in 97% of cases (70/72). A very low interlaboratory variability in Cq values (SD = 1.89 cycles) were observed. For panel 2 assessing 26 different protocols, the detection rates were high (77-100%) for 5/6 of spiked serum. There was a significant association between the qPCR platform and performance. However, certain technical steps and optimal combinations of factors may also impact performance. The good reproducibility and performance demonstrated in this study support the use of Mucorales qPCR as part of the diagnostic strategy for mucormycosis.

N-chlorotaurine, a potent weapon against multiresistant bacteria

Aims

N‐chlorotaurine (NCT) is a body‐own mild oxidizing antiseptic that can be applied topically as a well‐tolerated anti‐infective at many body sites. The objective of this study was to demonstrate its activity against representative nosocomial multidrug‐resistant bacteria.

Methods and Results

The bactericidal activity of NCT was tested in quantitative killing assays against a panel of multiresistant Gram‐positive and Gram‐negative clinical isolates. N‐chlorotaurine (1%, 55 mmol l⁻¹) reduced the number of CFU of strains of methicillin‐resistant Staphylococcus aureus, linezolid‐resistant Staphylococcus epidermidis, vancomycin‐resistant, and linezolid‐ and vancomycin‐resistant Enterococcus faecium, 3MRGN and 4MRGN Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii and Klebsiella pneumoniae by at least 2 log₁₀ steps after 15 min and completely or nearly to the detection limit after 30 min at pH 7·1 and 37°C.

Conclusion

The activity of NCT against these clinical isolates is similar to that against non‐resistant ATCC strains and therefore not influenced by antibiotic resistance. This can be explained by the oxidizing and chlorinating mechanism of action of NCT, which leads to an attack of multiple targets in the microorganisms.

Significance and Impact of the Study

The bactericidal spectrum of NCT is not restricted by resistance against antibiotics. Therefore, it can be used against resistant strains, too.

Devulcanization Technologies for Recycling of Tire-Derived Rubber: A Review

In general, composite materials are difficult to recycle. Tires belong to this class of materials. On top, one of their main constitutents, vulcanized rubber, is as elastomer, which cannot be remolten and hence is particularly challenging to put to a new use. Today, the main end-of-life routes of tires and other rubber products are landfilling, incineration in e.g., cement plants, and grinding to a fine powder, generating huge quantities and indicating a lack of sustainable recycling of this valuable material. True feedstock recycling is not feasible for complex mixtures such as tires, but devulcanization can be done to reactivate the cross-linked polymer for material recycling in novel rubber products. Devulcanization, i.e., the breaking up of sulfur bonds by chemical, thermophysical, or biological means, is a promising route that has been investigated for more than 50 years. This review article presents an update on the state-of-the art in rubber devulcanization. The article addresses established devulcanization technologies and novel processes described in the scientific and patent literatures. On the one hand, tires have become high-tech products, where the simultaneous improvement of wet traction, rolling resistance, and abrasion resistance (the so-called "magic triangle") is hard to achieve. On the other hand, recycling and sustainable end-of-life uses are becoming more and more important. It is expected that the public discussion of environmental impacts of thermoplastics will soon spill over to thermosets and elastomers. Therefore, the industry needs to develop and market solutions proactively. Every year, approximately 40 million tons of tires are discarded. Through the devulcanization of end-of-life tires (ELT), it is possible to produce new raw materials with good mechanical properties and a superior environmental footprint over virgin products. The devulcanization process has become an interesting technology that is able to support the circular economy concept.

Antifungal susceptibility testing in Candida, Aspergillus and Cryptococcus infections: are the MICs useful for clinicians?

BACKGROUND

Invasive fungal infections (IFIs) represent a global issue and affect various patient populations. In recent years, resistant fungal isolates showing increased azole or echinocandin MICs have been reported, and their potential clinical impact has been investigated.

AIMS

To provide an update on the epidemiology of resistance among fungi (e.g., Candida spp., Aspergillus spp., and Cryptococcus spp.) and to offer a critical appraisal of the relevant literature regarding the impact of MICs on clinical outcome in patients with IFI.

SOURCES

PubMed search with relevant keywords along with a personal collection of relevant publications.

CONTENT

Although antifungal resistance has been associated with a poorer response to antifungal therapy in various studies, other factors such as comorbidities, septic shock and source of infection appear to be key determinants affecting the clinical outcome of patients with IFI.

IMPLICATIONS

Future international collaborative studies are required to tease out the relative contribution of in vitro antifungal resistance on patient outcomes, thus enabling the optimization of IFI management.

Increased carbohydrate production from carbon dioxide in randomly mutated cells of cyanobacterial strain Synechocystis sp. PCC 6714: Bioprocess understanding and evaluation of productivities

Recently, several mutants of Synechocystis sp. PCC 6714 were obtained showing superior PHB content and productivities. Here, the most promising mutant named MT_a24 is compared in detail with the wild-type in controlled photobioreactors. In order to provide an easily scalable and alternative approach to the normally done two-step process -comprising of growth phase and limitation phase- a one-step cultivation was optimized. The multivariate experimental design approach was used for the optimization of the one-step, self-limiting media. During one-step cultivation of MT_a24 with optimized media 30 ± 4% (DCW) corresponding to 1.16 g L^-1 PHB was obtained. Using pulse experiments it was demonstrated that phosphate is the key driver of glycogen synthesis in Synechocystis sp. PCC 6714 and it can be used to boost glycogen productivity. The maximum glycogen content acquired was 2.6 g L^-1 (76.2% DCW) for mutant MT_a24 using phosphate feeding and carbon dioxide as carbon source.

Bioprocess Engineering Aspects of Sustainable Polyhydroxyalkanoate Production in Cyanobacteria

Polyhydroxyalkanoates (PHAs) are a group of biopolymers produced in various microorganisms as carbon and energy reserve when the main nutrient, necessary for growth, is limited. PHAs are attractive substitutes for conventional petrochemical plastics, as they possess similar material properties, along with biocompatibility and complete biodegradability. The use of PHAs is restricted, mainly due to the high production costs associated with the carbon source used for bacterial fermentation. Cyanobacteria can accumulate PHAs under photoautotrophic growth conditions using CO₂ and sunlight. However, the productivity of photoautotrophic PHA production from cyanobacteria is much lower than in the case of heterotrophic bacteria. Great effort has been focused to reduce the cost of PHA production, mainly by the development of optimized strains and more efficient cultivation and recovery processes. Minimization of the PHA production cost can only be achieved by considering the design and a complete analysis of the whole process. With the aim on commercializing PHA, this review will discuss the advances and the challenges associated with the upstream processing of cyanobacterial PHA production, in order to help the design of the most efficient method on the industrial scale.

Direct detection of Exophiala and Scedosporium species in sputa of patients with cystic fibrosis

Detection of species of Exophiala and Scedosporium in the respiratory tracts of cystic fibrosis (CF) patients remains controversial because of highly variable results. The results of our study suggested a significantly higher prevalence and more complex colonization than previously estimated. Approximately 17% (27/162) of clinical sputum samples were found to be positive for Exophiala dermatitidis and 30% (49/162) were positive for Scedosporium apiospermum / S. boydii species complex determined by reverse line blot (RLB) hybridization. In contrast, only 14.2% (23/162) and 1.2% (2/162) of clinical sputa were positive for E. dermatitidis and S. apiospermum / S. boydii species complex when tested by culture, respectively. Molecular detection methods, such as loop-mediated isothermal amplification (LAMP) or reverse line blot (RLB) hybridization, have the potential to become powerful alternatives to selective culture, providing a more realistic understanding on the prevalence of E. dermatitidis and S. apiospermum / S. boydii species complex in the respiratory tract of CF patients.

Increased poly-β-hydroxybutyrate production from carbon dioxide in randomly mutated cells of cyanobacterial strain Synechocystis sp. PCC 6714: Mutant generation and characterization

Photosynthetic Poly-β-hydroxybutyrate (PHB) productivity in cyanobacteria needs to be increased to make cyanobacterial derived bioplastics economically feasible and competitive with petroleum-based plastics. In this study, high PHB yielding mutants of Synechocystis sp. PCC 6714 have been generated by random mutagenesis, using UV light as a mutagen. The selection of strains was based on PHB content induced by nitrogen and phosphorus starvation. The fast growing mutant MT_a24 exhibited more than 2.5-fold higher PHB productivity than that of the wild-type, attaining values of 37 ± 4% dry cell weight PHB. The MT_a24 was characterized for phenotypes, CO₂ uptake rate and gene expression levels using quantitative PCR. Genome sequencing showed that UV mutagenesis treatment resulted in a point mutation in the ABC-transport complex, phosphate-specific transport system integral membrane protein A (PstA). The MT_a24 shows potential for industrial production of PHB and also for carbon capture from the atmosphere or point sources.

Photosynthetic poly-β-hydroxybutyrate accumulation in unicellular cyanobacterium Synechocystis sp. PCC 6714

Poly-β-hydroxybutyrate (PHB) production from CO₂ has the potential to reduce the production cost of this biodegradable polyesters, and also to make the material more sustainable compared to utilization of sugar feedstocks. In this study the unicellular cyanobacterium, Synechocystis sp. PCC 6714 has been identified as an unexplored potential organism for production of PHB. Synechocystis sp. PCC 6714 was studied under various cultivation conditions and nutritional limitations. Combined effects of nitrogen and phosphorus deficiency led to highest PHB accumulation under photoautotrophic conditions. Multivariate experimental design and quantitative bioprocess development methodologies were used to identify the key cultivation parameters for PHB accumulation. Biomass growth and PHB accumulation were studied under controlled defined conditions in a lab-scale photobioreactor. Specific growth rates were fourfold higher in photobioreactor experiments when cultivation conditions were controlled. After 14 days of cultivation in nitrogen and phosphorus, limited media intracellular PHB levels reached up to 16.4% from CO₂. The highest volumetric production rate of PHB was 59 ± 6 mg L⁻¹ day⁻¹. Scanning electron microscopy of isolated PHB granules of Synechocystis sp. PCC 6714 cultivated under nitrogen and phosphorus limitations showed an average diameter of 0.7 µm. The results of this study might contribute towards a better understanding of photoautotrophic PHB production from cyanobacteria.

A prospective international Aspergillus terreus survey: an EFISG, ISHAM and ECMM joint study

OBJECTIVES

A prospective international multicentre surveillance study was conducted to investigate the prevalence and amphotericin B susceptibility of Aspergillus terreus species complex infections.

METHODS

A total of 370 cases from 21 countries were evaluated.

RESULTS

The overall prevalence of A. terreus species complex among the investigated patients with mould-positive cultures was 5.2% (370/7116). Amphotericin B MICs ranged from 0.125 to 32 mg/L, (median 8 mg/L).

CONCLUSIONS

Aspergillus terreus species complex infections cause a wide spectrum of aspergillosis and the majority of cryptic species display high amphotericin B MICs.

Real-time monitoring of beta-d-glucuronidase activity in sediment laden streams: A comparison of prototypes

Detection of enzymatic activities has been proposed as a rapid surrogate for the culture-based microbiological pollution monitoring of water resources. This paper presents the results of tests on four fully automated prototype instruments for the on-site monitoring of beta-d-glucuronidase (GLUC) activity. The tests were performed on sediment-laden stream water in the Hydrological Open Air Laboratory (HOAL) during the period of March 2014 to March 2015. The dominant source of faecal pollution in the stream was swine manure applied to the fields within the catchment. The experiments indicated that instrument pairs with the same construction design yielded highly consistent results (R(2) = 0.96 and R(2) = 0.94), whereas the results between different designs were less consistent (R(2) = 0.71). Correlations between the GLUC activity measured on-site and culture-based Escherichia coli analyses over the entire study period yielded R(2) = 0.52 and R(2) = 0.47 for the two designs, respectively. The correlations tended to be higher at the event scale. The GLUC activity was less correlated with suspended sediment concentrations than with E. coli, which is interpreted in terms of indicator applicability and the time since manure application. The study shows that this rapid assay can yield consistent results over a long period of on-site operation in technically challenging habitats. Although the use of GLUC activity as a proxy for culture-based assays could not be proven for the observed habitat, the study results suggest that this biochemical indicator has high potential for implementation in early warning systems.

Abstract PD6-03: High prevalence and clonal heterogeneity of ESR1 mutations (mt) in circulating tumor DNA (ctDNA) from patients (pts) enrolled in FERGI, a randomized phase II study testing pictilisib (GDC-0941) in combination with fulvestrant (F) in pts that failed a prior aromatase inhibitor (AI)

Background: Mutations in the ligand binding domain of the estrogen receptor gene (ESR1) have been associated with resistance to AI therapy in pts with ER+ breast cancer. To assess if ESR1 status has prognostic or predictive significance in the post-AI metastatic setting ESR1 mutation status was analyzed in circulating tumor DNA (ctDNA) from 168 pts enrolled on the FERGI study (NCT01437566; Krop et al., SABCS 2014).

Methods: Baseline and longitudinal mutational analysis for hotspot mutations in ESR1 (E380Q, S463P, V534E, P535H, L536R/H/P, L536Q, Y537N/S/C, D538G) and PIK3CA (C420R, E542K, E545K/G, Q546K, M1043I, H1047Y/R/L) was performed using droplet digital PCR (ddPCR) on ctDNA derived from plasma. Archival tissue was analyzed via RT-PCR and ddPCR.

Results: Baseline ctDNA analysis demonstrated a total of 62/156 (40%) and 57/153 (37%) pts with PIK3CA and ESR1 mutations, respectively. The most common ESR1 mutations are D538G, Y537S, and E380Q, representing 54%, 33% and 26% of the pts with a detectable ESR1 mutation at baseline, respectively. There was a numeric increase of ESR1 mutations in patients with LumA (41/99, 41%) vs LumB disease (14/44, 31%). PIK3CA mutations in asynchronously collected archival tissue were 85% concordant with plasma ctDNA mutations (sensitivity 78%, specificity 91%). PIK3CA mutations in baseline ctDNA showed a higher median allele frequency (AF) than ESR1 mutations (3.6% vs 0.46%), consistent with PIK3CA being an early event and ESR1 mutations occurring later in pts with recurrent disease. Of the pts with a detectable ESR1 mutation at baseline (n=57), 23 (40%) pts had multiple ESR1 mutations and 10 (18%) had ≥3 ESR1 mutations. The PFS outcomes for patients with and without ESR1 mutations detected at baseline are summarized below, indicating no obvious prognostic or predictive effect for combination of F with pictilisib compared with F in these underpowered subsets.

ArmESR1 MT - mPFS (mo)ESR1 WT - mPFS (mo)HR (95% CI)F + placebo5.4 (30 pts, 24 events)3.7 (40 pts, 31 events)1.06 (0.62, 1.81)F+pictilisib5.8 (27 pts, 20 events)6.7 (56 pts, 34 events)1.36 (0.78, 2.38)

PIK3CA and ESR1 ctDNA analysis on serial plasma samples from 40 pts and the assessment of ESR1 mutation status in the patient's tumor sample by ddPCR is currently in progress and will be reported.

Conclusions: Mutations in ESR1 detected by ddPCR in patient plasma samples occur in nearly 40% of pts that failed a prior AI. The polyclonal nature of ESR1 mutations is consistent with the convergent evolution of multiple AI resistant subclones. While these conclusions should be interpreted with caution due to the relatively small sample size and post hoc nature of the analysis, this data does not support a prognostic or predictive PFS hypothesis for ESR1 mutations with F or in combination with pictilisib.

Citation Format: Spoerke J, Gendreau S, Johnston S, Schmid P, Krop I, Qui J, Derynck M, Chan I, Walter K, Amler L, Hampton G, Lackner M. High prevalence and clonal heterogeneity of ESR1 mutations (mt) in circulating tumor DNA (ctDNA) from patients (pts) enrolled in FERGI, a randomized phase II study testing pictilisib (GDC-0941) in combination with fulvestrant (F) in pts that failed a prior aromatase inhibitor (AI). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr PD6-03.

Geographically predominant genotypes of Aspergillus terreus species complex in Austria: s microsatellite typing study

Aspergillus terreus species complex is recognized as a frequent agent of invasive aspergillosis in Tyrol. The reason for this specific epidemiological situation is unclear. Aspergillus terreus strains isolated from environmental and clinical sources were genotyped using a novel panel of short tandem repeats and were evaluated for virulence. Three major endemic genotypes collected from the Inn region and its side valleys were found to cause the majority of invasive A. terreus infections. All of these genotypes were of the same mating type, which suggests that a mating barrier is present between these geographically well-adapted strains which is found to persist for at least 11 years. The three major genotypes were prevalent in both human infections and the environment. No major differences in virulence were observed using Galleria mellonella as model. Our data suggest a specific environmental exposure being responsible for the high incidence of A. terreus infections in Innsbruck, the Inn valley and side valleys (Tyrol, Austria).

Identification of Endoglin as an epigenetically regulated tumour-suppressor gene in lung cancer

Background:

The transforming growth factor-beta (TGF- β) pathway has been implicated in proliferation, migration and invasion of various cancers. Endoglin is a TGF-β accessory receptor that modulates signalling. We identified Endoglin as an epigenetically silenced tumour-suppressor gene in lung cancer by means of a genome-wide screening approach, then sought to characterise its effect on lung cancer progression.

Methods:

Methylation microarray and RNA sequencing were carried out on lung cancer cell lines. Epigenetic silencing of Endoglin was confirmed by methylation and expression analyses. An expression vector and a 20-gene expression panel were used to evaluate Endoglin function. Pyrosequencing was carried out on two independent cohorts comprising 112 and 202 NSCLC cases, respectively, and the impact of Endoglin methylation on overall survival (OS) was evaluated.

Results:

Methylation in the promoter region resulted in silencing of Endoglin, which could be reactivated by demethylation. Increased invasion coupled with altered EMT marker expression was observed in cell lines with an epithelial-like, but not those with a mesenchymal-like, profile when Endoglin was absent. Methylation was associated with decreased OS in stage I but not in stages II–III disease.

Conclusions:

We show that Endoglin is a common target of epigenetic silencing in lung cancer. We reveal a link between Endoglin silencing and EMT progression that might be associated with decreased survival in stage I disease.

ESCMID and ECMM joint guidelines on diagnosis and management of hyalohyphomycosis: Fusarium spp., Scedosporium spp. and others

Mycoses summarized in the hyalohyphomycosis group are heterogeneous, defined by the presence of hyaline (non-dematiaceous) hyphae. The number of organisms implicated in hyalohyphomycosis is increasing and the most clinically important species belong to the genera Fusarium, Scedosporium, Acremonium, Scopulariopsis, Purpureocillium and Paecilomyces. Severely immunocompromised patients are particularly vulnerable to infection, and clinical manifestations range from colonization to chronic localized lesions to acute invasive and/or disseminated diseases. Diagnosis usually requires isolation and identification of the infecting pathogen. A poor prognosis is associated with fusariosis and early therapy of localized disease is important to prevent progression to a more aggressive or disseminated infection. Therapy should include voriconazole and surgical debridement where possible or posaconazole as salvage treatment. Voriconazole represents the first-line treatment of infections due to members of the genus Scedosporium. For Acremonium spp., Scopulariopsis spp., Purpureocillium spp. and Paecilomyces spp. the optimal antifungal treatment has not been established. Management usually consists of surgery and antifungal treatment, depending on the clinical presentation.

Positions and numbers of FKS mutations in Candida albicans selectively influence in vitro and in vivo susceptibilities to echinocandin treatment

Candidemia is the fourth most common kind of microbial bloodstream infection, with Candida albicans being the most common causative species. Echinocandins are employed as the first-line treatment for invasive candidiasis until the fungal species is determined and confirmed by clinical diagnosis. Echinocandins block the FKS glucan synthases responsible for embedding β-(1,3)-d-glucan in the cell wall. The increasing use of these drugs has led to the emergence of antifungal resistance, and elevated MICs have been associated with single-residue substitutions in specific hot spot regions of FKS1 and FKS2. Here, we show for the first time the caspofungin-mediated in vivo selection of a double mutation within one allele of the FKS1 hot spot 1 in a clinical isolate. We created a set of isogenic mutants and used a hematogenous murine model to evaluate the in vivo outcomes of echinocandin treatment. Heterozygous and homozygous double mutations significantly enhance the in vivo resistance of C. albicans compared with the resistance seen with heterozygous single mutations. The various FKS1 hot spot mutations differ in the degree of their MIC increase, substance-dependent in vivo response, and impact on virulence. Our results demonstrate that echinocandin EUCAST breakpoint definitions correlate with the in vivo response when a standard dosing regimen is used but cannot predict the in vivo response after a dose escalation. Moreover, patients colonized by a C. albicans strain with multiple mutations in FKS1 have a higher risk for therapeutic failure.

Abstract P6-09-01: Central Ki67 analysis as a predictor for adjuvant capecitabine efficacy in early breast cancer (EBC) subtypes in US oncology trial 01062

Background: USON 01062 (O’Shaughnessy J, et al. Proc SABCS, 2010, abst S4-2) showed no improvement in the primary endpoint of disease-free survival (DFS) (median FU 5 yrs: HR 0.84, 95% CI: 0.67-1.05; p = 0.125) with the addition of capecitabine (X) to standard adjuvant chemotherapy, but showed improvement in OS (HR 0.68, 95% CI: 0.51-0.92; p = 0.011). Exploratory analysis of local pathology-assessed Ki67 suggested benefit from adjuvant X in pts with more highly proliferative cancers with Ki67 ≥ 10% (Pippen J et al. Proc ASCO, 2011, abst 500). The objective of this study is to determine whether centrally-performed Ki67 IHC results corroborate or refute this finding.

Methods: 2610 pts with resected high risk EBC were randomized to receive 4 cycles of AC (doxorubicin 60mg/m2 and cyclophosphamide 600mg/m2) IV every 3 wks for 4 cycles followed by either docetaxel 100mg/m2 IV or docetaxel 75mg/m2 IV plus X 825mg/m2 PO bid for 14 days every 3 wks for 4 cycles. Archival primary breast cancer tissue was collected on 2000 pts for predictive biomarker analyses. Central Ki67 IHC was performed using the anti-Ki67 monoclonal antibody SP6 and was read by one pathologist (HK) according to published recommendations (Dowsett M, et al. JNCI 103:1-9, 2011).

Results: Central Ki67 IHC has been performed on 1440 pts who had centrally-validated informed consents. The distribution of% Ki67-positive cells by locally-assessed ER/HER2 subtype is shown below. 45% of HR+ HER2- BCs had a Ki67 ≤ 10%, while 24% had a Ki67 11% to 20%, and 31% had a Ki67 &gt; 20%. The concordance between the local vs central Ki67 results was low at 46% for Ki67 &lt;10%, 49% for Ki67 10%-20%, and 76% for Ki67 &gt; 20%. The central Ki67 results tended to be higher than the local testing results. Central mRNA classifiers were developed for ER, PR, HER2 and Ki67 using Fluidigm Microfluidics Dynamic Arrays and correlate highly with central IHC assessment of these markers.

Conclusions: HR+ HER2- EBC is enriched for cancers with a low proliferative rate, a group of pts unlikely to benefit from the cell cycle-specific cytotoxic agent, capecitabine. Analyses of the impact of adjuvant X added to AC/T in EBC pts according to ER status, and according to Ki67 (analyzed as a binary and continuous variable) will be performed prior to SABCS, 2013.

Number of Patients% Ki67 Pos CellsTotal *HR+TNHER2+/HR+HER2+/ HR-0-104163622222711-151391066151016-20126871615821-3018411539201031-1005751403423555Total144081042510790*Totals do not equal sum of subtype categories due to missing HER2 information

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-09-01.

Abstract P4-06-10: Epigenetic silencing of glutamine synthetase (Glul) defines glutamine depletion therapy

Background: Methylation-dependent transcriptional silencing of genes involved in amino acid synthesis can provide potential targets for novel synthetic lethality strategies. Glutamine synthetase (Glul) is the key enzyme in the biosynthesis of glutamine. We identified Glul as a novel gene subject to methylation-dependent transcriptional silencing in breast cancer cell lines using a combined functional screen with methylation reversal assays and methylation arrays.

Methods: Methylation reversal assays were performed using 5-aza-2-deoxycytidine and/or trichostatin treatment coupled with whole genome mRNA microarrays (Illumina HT-12 v4 Expression BeadChip Kit). Expression of Glul with and without pharmacological methylation reversal with azacytidine and/or trichostatin was validated using qRT-PCR and Western Blot. Methylation of Glul was analysed using methylation microarrays (Illumina 450K Methylation BeadChip), bisulphite sequencing and pyrosequencing. Sensitivity to glutamine deprivation was assessed using an MTT assay after culturing cells in media with various glutamine concentrations or in complete absence of glutamine. We used a panel of 55 breast cancer cell lines and formalin-fixed paraffin-embedded tissue from a series of 116 stage I-III primary breast cancers with linked mature clinical outcome data that were randomly selected from the Cuneo Tissue Bank. Tissue samples were subject to histopathological review to ensure adequate representation of cancer cells.

Results: Dense methylation of the CpG-island of Glul was detected in 45% of cell lines across all subtypes. Methylation of the CpG island was linked with absent or down-regulated expression of Glul in some but not all cell lines, and Glul expression could be reactivated by azacytidine and trichostatin in these cell lines. Methylation of shore areas was detected in several cell lines but was not associated with transcriptional silencing. Cells with methylation-dependent low or absent Glul expression were highly sensitive to glutamine deprivation, whereas cell lines without Glul methylation were rescued by compensatory up-regulation of Glul. Using pyrosequencing, dense methylation of the CpG island of Glul was found in 32.8% of patients, with an additional 17.2% of patients showing partial methylation. No significant association with a specific breast cancer subtype or outcome was found.

Conclusions: This is the first report of methylation-dependent transcriptional silencing of Glul expression in cancer. Our data demonstrate that a significant proportion of primary breast cancers show methylation of Glul and suggest that glutamine deprivation could be a novel synthetic lethality strategy for these cancers.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-06-10.

Infection and colonisation due to Scedosporium in Northern Spain. An in vitro antifungal susceptibility and molecular epidemiology study of 60 isolates

Since the latest taxonomical changes in the genus Scedosporium by Gilgado et al. in 2010, no species-specific studies on epidemiology and antifungal susceptibility patterns (AFSP) have so far been published. This study aimed to provide qualitative epidemiological data of Scedosporium spp. isolated from cystic fibrosis (CF) patients and immunocompromised patients from Northern Spain. Isolates were identified by using amplified fragment length polymorphism (AFLP), and species-specific AFSP were generated for all currently available antifungal compounds. AFLP was a useful tool for identification to species-level and for the discrimination of inter- and intra-patient isolates. Scedosporium prolificans represents the most prevalent species in the respiratory tract of CF patients and immunocompromised patients in Northern-Spain, followed by Pseudallescheria boydii, P. apiosperma, and P. ellipsoidea. CF patients were exclusively colonised with either P. boydii or S. prolificans. Patients were colonised over years exclusively with isolates affiliated to one species, but some patients were colonised with multiple strains with different AFSP. The sum of those co-colonising strains in one patient, may appear in vitro and in vivo as a multi-resistant S. prolificans isolate, as strains are morphologically identical and might therefore be regarded as only one strain. A majority of Scedosporium strains (with exception of S. prolificans) were found susceptible for voriconazole and micafungin.

Severe prosthetic joint infection in an immunocompetent male patient due to a therapy refractory Pseudallescheria apiosperma

Prosthetic joint infections (PJI) are rarely due to fungal agents and if so they are mainly caused by Candida strains. This case represents a PJI caused by a multi-drug resistant Pseudallescheria apiosperma, with poor in vivo response to itraconazole and voriconazole. This case differs also by the way of infection, since the joint infection did not follow a penetrating trauma. In the majority of cases, Scedosporium extremity infections remain local in immunocompetent individuals. We report a persistent joint infection with multiple therapeutic failures, and subsequent amputation of the left leg. Detailed clinical data, patient history, treatment regime and outcome of a very long-lasting (>4 years) P. apiosperma prosthetic knee infection in an immunocompetent, 61-year-old male patient are presented with this case. The patient was finally cured by the combination of multiple and extensive surgical interventions and prolonged antifungal combination therapy with voriconazole and terbinafine.