Analysis of CRISPR-Cas Loci and their Targets in Levilactobacillus brevis.

The CRISPR‒Cas system acts as a bacterial defense mechanism by conferring adaptive immunity and limiting genetic reshuffling. However, under adverse environmental hazards, bacteria can employ their CRISPR‒Cas system to exchange genes that are vital for adaptation and survival. Levilactobacillus brevis is a lactic acid bacterium with great potential for commercial purposes because it can be genetically manipulated to enhance its functionality and nutritional value.

Characterization of class 1 integron gene cassettes among clinical bacteria isolated from one large hospital in northern China.

The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 integrons containing gene cassettes widely distributed among gram negative clinical isolates was observed. We find that the class 1 integron showed positive correlation with multidrug resistance phenotype of gram negative bacteria.

Association study of angiotensin converting enzyme gene polymorphism with elderly diabetic hypertension and lipids levels.

Objective: To investigate the relationship between angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism and diabetic essential hypertension in elderly population.

Methods: Polymerase chain reaction (PCR) technique was used in 260 elderly normal control patients, 205 elderly hypertensive patients and 138 elderly diabetic hypertensive patients to detect the I/D polymorphism in ACE gene.

Results: DD genotype frequency (0.

Involvement of SigT and RstA in the differentiation of Streptomyces coelicolor.

SigT is an ECF sigma factor in Streptomyces coelicolor. sigT and its putative anti-sigma factor gene rstA are located in one putative operon, and SigT could physically interact with RstA. Deletion of sigT or rstA caused accelerated morphological development and enhanced production of antibiotics, concomitant with over-expression of chpE, chpH, actII-orf4 and redD.

Reciprocal regulation between SigK and differentiation programs in Streptomyces coelicolor.

Here we reported that deletion of SigK (SCO6520), a sigma factor in Streptomyces coelicolor, caused an earlier switch from vegetative mycelia to aerial mycelia and higher expression of chpE and chpH than that in the wild type. Loss of SigK also resulted in accelerated and enhanced production of antibiotics, actinorhodin, and undecylprodigiosin and increased expression of actII-orf4 and redD. These results suggested that SigK had a negative role in morphological transition and secondary metabolism.

New approach to achieve high-level secretory expression of heterologous proteins by using Tat signal peptide.

The twin-arginine translocation (Tat) pathway is an attractive route for secretory production of heterologous proteins in E. coli. In this study, we investigated the potential use of Tat signal peptide from S.

Roles of larger conductance mechanosensitive channels (MscL) in sporulation and Act secretion in Streptomyces coelicolor.

Larger conductance mechanosensitive channels (MscL) is a conserved channel existing in eukarya, bacteria and archaea. The gene SCO3190 in Streptomyces coelicolor encodes an MscL homolog of Escherichia coli. To elucidate the physiological roles of MscL in S.

FtsY affects sporulation and antibiotic production by whiH in Streptomyces coelicolor.

FtsY, the Signal Recognition Particle (SRP) receptor in bacteria, is known to facilitate the cotranslational protein targeting by recruiting SRP-protein complex to secYEG. We show in this work that deletion of the ftsY gene in Streptomyces coelicolor would also lead to complete blockage of sporulation process and reduced production of antibiotic actinorhodin. These defects cannot be complemented by only the NG domain of FtsY, while full-length ftsY was able to restore spore generation and increase production of actinorhodin in ftsY-disrupted strains.

[Preparation of monodispersed agglomerated pellicular cation exchange resins and its chromatographic properties].

A new and simple method for the preparation of latex-coated pellicular cation exchanger is introduced. Chromatographic stationary phase of monodispersed agglomerated pellicular cation was prepared for the first time. The monodispersed polyvinylbenzene-divinylbenzene (PSTDVB) particles (10 microns) as substrate beads were functionalized with a tertiary amine on the surface at first and then attached with a layer of sulfonated latex particles (0.