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Synucleinopathies are neurodegenerative diseases that are associated with the misfolding and aggregation of α-synuclein, including Parkinson's disease, dementia with Lewy bodies and multiple system atrophy 1 . Clinically, it is challenging to differentiate Parkinson's disease and multiple system atrophy, especially at the early stages of disease 2 . Aggregates of α-synuclein in distinct synucleinopathies have been proposed to represent different conformational strains of α-synuclein that can self-propagate and spread from cell to cell 3-6 . Protein misfolding cyclic amplification (PMCA) is a technique that has previously been used to detect α-synuclein aggregates in samples of cerebrospinal fluid with high sensitivity and specificity 7,8 . Here we show that the α-synuclein-PMCA assay can discriminate between samples of cerebrospinal fluid from patients diagnosed with Parkinson's disease and samples from patients with multiple system atrophy, with an overall sensitivity of 95.4%. We used a combination of biochemical, biophysical and biological methods to analyse the product of α-synuclein-PMCA, and found that the characteristics of the α-synuclein aggregates in the cerebrospinal fluid could be used to readily distinguish between Parkinson's disease and multiple system atrophy. We also found that the properties of aggregates that were amplified from the cerebrospinal fluid were similar to those of aggregates that were amplified from the brain. These findings suggest that α-synuclein aggregates that are associated with Parkinson's disease and multiple system atrophy correspond to different conformational strains of α-synuclein, which can be amplified and detected by α-synuclein-PMCA. Our results may help to improve our understanding of the mechanism of α-synuclein misfolding and the structures of the aggregates that are implicated in different synucleinopathies, and may also enable the development of a biochemical assay to discriminate between Parkinson's disease and multiple system atrophy.

Polythene is the most widely used plastic around the globe. Among the total plastic waste generated, polythene contributes the maximum share (64%). Various strategies/methods are being utilized to deal with the increasing rate of plastic waste, but among all the methods, bioremediation is regarded as the ecofriendly and widely accepted method. In the current investigation, we have attempted to discover the elite polythene deteriorating fungi (isolated from the rhizosphere soil of Avicennia marina). From 12 different eco-geographical locations along the West Coast of India, total 109 fungal isolates were recorded. The polythene deteriorating fungi were screened at varied pH (3.5, 7 and 9.5) based on changes in weight and tensile strength of the treated polythene at ambient temperature with continuous shaking for 60 days. BAYF5 isolate (pH 7) results in maximum reduction in weight (58.51 ± 8.14) whereas PNPF15 (pH 3.5) recorded highest reduction in tensile strength (94.44 ± 2.40). Surprisingly, we have also reported weight gain, with highest percent weight gain (28.41 ± 6.99) with MANGF13 at pH 9.5. To test the reproducibility of the results, the elite polythene degrading fungal isolates based on weight loss and reduction in tensile strength were only used for repetition experiment and the results based on the reduction in tensile strength were found only reproducible. Polythene biodegradation was further confirmed using Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) analysis. The most efficient polythene deteriorating fungal isolates were identified as Aspergillus terreus strain MANGF1/WL and Aspergillus sydowii strain PNPF15/TS using both morphological keys and molecular tools.

Polythene-degradation products (PE-DPs) produced due to two most efficient polythene degrading fungal isolates (Aspergillus terreus strain MANF1/WL and Aspergillus sydowii strain PNPF15/TS) after 60 days of incubation at ambient temperature with continuous shaking were analyzed by employing GC-MS method. Total 24 PE-DPs were recorded in total 4 samples i) control (pH 3.5), ii) Treatment of Aspergillus terreus strain MANF1/WL (pH 3.5), iii) control (pH 9.5) and iv) Treatment of Aspergillus sydowii strain PNP15/TS (pH 9.5). To check the deleterious status of PE-DPs using both the elite fungal isolates at in vitro level, two living systems (Sorghum and Tiger shark) were used. The percent germination rate of sorghum seeds were found unaffected with PE-DPs of both elite fungi. PE-DPs of both the fungal isolates exhibited maximum germination index at 50%. Whereas, highest elongation inhibition rate (34.75 ± 7.10) was reported with PE-DPs of Aspergillus terreus strain MANF1/WL. In case of animals system, no mortality of the Tiger sharks was documented after fifteen days of the treatment.

Microcin E492 (Mcc) is a pore-forming bacteriotoxin. Mcc activity is inhibited at the stationary phase by formation of amyloid-like aggregates in the culture. Here we report that, in a similar manner as prions, Mcc naturally exists as two conformers: a β-sheet-rich, protease-resistant, aggregated, inactive form (Mcc ia ), and a soluble, protease-sensitive, active form (Mcc a ). The exogenous addition of culture medium containing Mcc ia or purified in vitro-generated Mcc ia into the culture induces the rapid and efficient conversion of Mcc a into Mcc ia , which is maintained indefinitely after passaging, changing the bacterial phenotype. Mcc ia prion-like activity is conformation-dependent and could be reduced by immunodepleting Mcc ia . Interestingly, an internal region of Mcc shares sequence similarity with the central domain of the prion protein, which is key to the formation of mammalian prions. A synthetic peptide spanning this sequence forms amyloid-like fibrils in vitro and is capable of inducing the conversion of Mcc a into Mcc ia in vivo, suggesting that this region corresponds to the prion domain of Mcc. Our findings suggest that Mcc is the first prokaryotic protein with prion properties which harnesses prion-like transmission to regulate protein function, suggesting that propagation of biological information using a prion-based conformational switch is an evolutionary conserved mechanism.