Liquid-crystalline ordering in bacterial cellulose produced by Gluconacetobaсter hansenii on glucose-containing media.

This research is dedicated to the studies of the microscale morphology of bacterial cellulose (BC) obtained by means of static cultivation of Gluconacetobacter hansenii GH-1/2008. We found that the microscale morphology depended on the BC production rate that was varied by using different glucose concentrations in the cultivation medium. It was revealed that at higher production rates, BC fibrils were aligned in a liquid-crystalline-like (LC-like) order.

Structural organization of bacterial cellulose: The origin of anisotropy and layered structures.

In this paper, we perform a systematic analysis of the structural organization of bacterial cellulose (BC). We report four types of organization of the BC mass, produced by Gluconacetobacter hansenii that occur depending on cultivation conditions. Two of those, particularly, plywood type one and layers of micro-sized tubes were observed and described for the first time.

Chitosan coatings with enhanced biostability in vivo.

In this article, we study the stability of chitosan coatings applied on glutaraldehyde-stabilized bovine pericardium when exposed to biodegradation in vivo in the course of model subcutaneous tests on rats. The coatings were deposited from carbonic acid solutions, that is, H O saturated with CO at high pressure. Histological sections of treated pericardium samples demonstrated that the structure of pericardial connective tissues was not significantly altered by the coating application method.

Microbial surfaces investigated using atomic force microscopy.

This paper is dedicated to atomic force microscopy (AFM) as a progressive tool for imaging bacterial surfaces and probing their properties. The description of the technique is complemented by the explanation of the method's artifacts typical, in particular, for the imaging of bacterial cells. Sample preparation techniques are summarized in a separate section.

Structural organization of mRNA complexes with major core mRNP protein YB-1.

YB-1 is a universal major protein of cytoplasmic mRNPs, a member of the family of multifunctional cold shock domain proteins (CSD proteins). Depending on its amount on mRNA, YB-1 stimulates or inhibits mRNA translation. In this study, we have analyzed complexes formed in vitro at various YB-1 to mRNA ratios, including those typical for polysomal (translatable) and free (untranslatable) mRNPs.

AFM study of potato virus X disassembly induced by movement protein.

Recently we have reported that a selective binding of potato virus X (PVX)-coded movement protein (termed TGBp1 MP) to one end of a polar coat protein (CP) helix converted viral RNA into a translatable form and induced a linear destabilization of the whole helical particle. Here, the native PVX virions, RNase-treated (PVX(RNA-DEG)) helical particles lacking intact RNA and their complexes with TGBp1 (TGBp1-PVX and TGBp1-PVX(RNA-DEG)), were examined by atomic force microscopy (AFM). When complexes of the TGBp1 MP with PVX were examined by means of AFM in liquid, no structural reorganization of PVX particles was observed.