6 research outputs found
Characterization of cytochrome P450 monooxygenase CYP154H1 from the thermophilic soil bacterium Thermobifida fusca
Cytochrome P450 monooxygenases are valuable biocatalysts due to their ability to hydroxylate unactivated carbon atoms using molecular oxygen. We have cloned the gene for a new cytochrome P450 monooxygenase, named CYP154H1, from the moderately thermophilic soil bacterium Thermobifida fusca. The enzyme was overexpressed in Escherichia coli at up to 14% of total soluble protein and purified to homogeneity in three steps. CYP154H1 activity was reconstituted using putidaredoxin reductase and putidaredoxin from Pseudomonas putida DSM 50198 as surrogate electron transfer partners. In biocatalytic reactions with different aliphatic and aromatic substrates of varying size, the enzyme converted small aromatic and arylaliphatic compounds like ethylbenzene, styrene, and indole. Furthermore, CYP154H1 also accepted different arylaliphatic sulfides as substrates chemoselectively forming the corresponding sulfoxides and sulfones. The enzyme is moderately thermostable with an apparent melting temperature of 67°C and exhibited still 90% of initial activity after incubation at 50°C
Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines
The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points
Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines
The last decade has seen a sharp increase in the number
of scientific publications describing physiological and
pathological functions of extracellular vesicles (EVs), a
collective term covering various subtypes of cell-released,
membranous structures, called exosomes, microvesicles,
microparticles, ectosomes, oncosomes, apoptotic bodies, and many
other names. However, specific issues arise when working with
these entities, whose size and amount often make them difficult
to obtain as relatively pure preparations, and to characterize
properly. The International Society for Extracellular Vesicles
(ISEV) proposed Minimal Information for Studies of Extracellular
Vesicles ("MISEV") guidelines for the field in 2014. We now
update these "MISEV2014" guidelines based on evolution of the
collective knowledge in the last four years. An important point
to consider is that ascribing a specific function to EVs in
general, or to subtypes of EVs, requires reporting of specific
information beyond mere description of function in a crude,
potentially contaminated, and heterogeneous preparation. For
example, claims that exosomes are endowed with exquisite and
specific activities remain difficult to support experimentally,
given our still limited knowledge of their specific molecular
machineries of biogenesis and release, as compared with other
biophysically similar EVs. The MISEV2018 guidelines include
tables and outlines of suggested protocols and steps to follow
to document specific EV-associated functional activities.
Finally, a checklist is provided with summaries of key points