Biotechnological process for obtaining compositions of plant proteins with transglutaminase enzyme

В данной работе проведена оптимизация параметров биодеструкции мультибелковых полимеров горохового, рисового и овсяного сырья с подбором состава композиций для поступления полноценного белка в организм человека и расширения использования данного белкового продукта в производстве пищевых изделий. In this work, the optimization of the parameters of biodegradation of multi-protein polymers of pea, rice and oat raw materials is carried out with the selection of the composition of the compositions for the intake of complete protein in the human body and the expansion of the use of this protein product in the manufacture of food products.

Pseudomonas aeruginosa PA14 produces R-bodies, extendable protein polymers with roles in host colonization and virulence

R-bodies are long, extendable protein polymers formed in the cytoplasm of some bacteria; they are best known for their role in killing of paramecia by bacterial endosymbionts. Pseudomonas aeruginosa PA14, an opportunistic pathogen of diverse hosts, contains genes (referred to as the reb cluster) with potential to confer production of R-bodies and that have been implicated in virulence. Here, we show that products of the PA14 reb cluster associate with R-bodies and control stochastic expression of R-body structural genes. PA14 expresses reb genes during colonization of plant and nematode hosts, and R-body production is required for full virulence in nematodes. Analyses of nematode ribosome content and immune response indicate that P. aeruginosa R-bodies act via a mechanism involving ribosome cleavage and translational inhibition. Our observations provide insight into the biology of R-body production and its consequences during P. aeruginosa infection.

Diverse LXG toxin and antitoxin systems specifically mediate intraspecies competition in Bacillus subtilis biofilms

Biofilms are multispecies communities, in which bacteria constantly compete with one another for resources and niches. Bacteria produce many antibiotics and toxins for competition. However, since biofilm cells exhibit increased tolerance to antimicrobials, their roles in biofilms remain controversial. Here, we showed that Bacillus subtilis produces multiple diverse polymorphic toxins, called LXG toxins, that contain N-terminal LXG delivery domains and diverse C-terminal toxin domains. Each B. subtilis strain possesses a distinct set of LXG toxin–antitoxin genes, the number and variation of which is sufficient to distinguish each strain. The B. subtilis strain NCIB3610 possesses six LXG toxin–antitoxin operons on its chromosome, and five of the toxins functioned as DNase. In competition assays, deletion mutants of any of the six LXG toxin–antitoxin operons were outcompeted by the wild-type strain. This phenotype was suppressed when the antitoxins were ectopically expressed in the deletion mutants. The fitness defect of the mutants was only observed in solid media that supported biofilm formation. Biofilm matrix polymers, exopolysaccharides and TasA protein polymers were required for LXG toxin function. These results indicate that LXG toxin-antitoxin systems specifically mediate intercellular competition between B. subtilis strains in biofilms. Mutual antagonism between some LXG toxin producers drove the spatial segregation of two strains in a biofilm, indicating that LXG toxins not only mediate competition in biofilms, but may also help to avoid warfare between strains in biofilms. LXG toxins from strain NCIB3610 were effective against some natural isolates, and thus LXG toxin–antitoxin systems have ecological impact. B. subtilis possesses another polymorphic toxin, WapA. WapA had toxic effects under planktonic growth conditions but not under biofilm conditions because exopolysaccharides and TasA protein polymers inhibited WapA function. These results indicate that B. subtilis uses two types of polymorphic toxins for competition, depending on the growth mode.