Triblock copolymeric nanoreactors are introduced as an alternative for liposomes as encapsulating carrier for prodrug activating enzymes. Inosine-adenosine-guanosine preferring nucleoside hydrolase of Trypanosoma vivax, a potential prodrug activating enzyme, was encapsulated in nanometer-sized vesicles constructed of poly(2-methyloxazoline)-block-poly(dimethylsiloxane)-block-(2-methyloxazoline)...

Recently solved outer membrane protein structures include the smallest and largest known beta-barrel structures, with functions distinct from the general and specific porins. Both protein expressed in outer membranes and protein deposited as cytoplasmic aggregates have been used for the structure determinations. As most beta-barrel proteins can be overexpressed in an aggregated form (inclusion ...

Two major outer membrane proteins of Enterobacter cloacae 206 were purified and identified as porins by using reconstituted vesicles. The 37-kilodalton porin forms a channel with a radius of 0.6 nm, which prefers positively charged substances to negatively charged ones, whereas the 39- to 40-kilodalton porin forms a larger channel with a radius of 0.8 nm, which has weaker selectivity for electr...

Four spontaneous, single-step mutants of Escherichia coli K-12 resistant to low levels of the cephalosporin 3'-quinolone ester Ro 23-9424 were isolated at a frequency of 10(-10) to 10(-11) mutants per CFU plated. The mutants were cross-resistant to both cephalosporin (cefotaxime) and quinolone (fleroxacin) components. Accordingly, they had altered porins and replicative DNA biosynthesis resista...