Chelation of Zinc with Biogenic Amino Acids: Description of Properties Using Balaban Index, Assessment of Biological Activity on Spirostomum Ambiguum Cellular Biosensor, Influence on Biofilms and Direct Antibacterial Action.

The complexation of biogenic molecules with metals is the widespread strategy in screening for new pharmaceuticals with improved therapeutic and physicochemical properties. This paper demonstrates the possibility of using simple QSAR modeling based on topological descriptors for chelates study. The presence of a relationship between the structure (J) and lipophilic properties (logP) of zinc complexes with amino acids, where two molecules coordinate the central atom through carboxyl oxygen and amino group nitrogen, and thus form a double ring structure, was predicted. Using a cellular biosensor model for Gly, Ala, Met, Val, Phe and their complexes Zn(AA)2, we experimentally confirmed the existence of a direct relationship between logP and biological activity (Ea). The results obtained using topological analysis, Spirotox method and microbiological testing allowed us to assume and prove that the chelate complex of zinc with methionine has the highest activity of inhibiting bacterial biofilms, while in aqueous solutions it does not reveal direct antibacterial effect.

Antibacterial Activity of Medicinal Plants against Uropathogenic Escherichia coli.

Urinary tract infections (UTIs) are one of the most common bacterial infections with uropathogenic Escherichia coli (UPEC) being the most prevalent causative agent in both complicated and uncomplicated UTIs. Antibiotic resistance among UPEC has been already demonstrated against a wide variety of antibiotics and the situation is continuing to deteriorate increasing the rate of recurrence and the difficulty of treatment and prophylaxis. Recently, a big attention has been paid to non-antibiotic approaches as an alternative to conventional antibiotics. Among many strategies, phytotherapy has gained a special attention worldwide. Herbal remedies have been used in traditional medicine since ancient times and they are well known for their effectiveness in treating many health conditions including UTIs. Researches are conducted continuously to validate the use of many medicinal plants against UPEC, investigate their mechanisms of action, and determine their active constituents. Our extensive review of the recent literature revealed that many phytochemicals are shown to target and inhibit a wide variety of bioprocesses in UPEC, such as adhesion, motility, biofilm formation, and quorum sensing. Such natural approaches are very promising in confronting the antibiotic resistance of UPEC and can be further used to develop plant-based strategies and pharmaceutical products to treat and prevent UTIs caused by UPEC.

Diplocloster agilis gen. nov., sp. nov. and Diplocloster modestus sp. nov., two novel anaerobic fermentative members of Lachnospiraceae isolated from human faeces.

Three novel strains of Gram-stain-negative, obligately anaerobic, spore-forming straight or slightly curved rods with pointed ends occurring singly or in pairs were isolated from the faeces of healthy human children. The strains were characterized by mesophilic fermentative metabolism and production of acetate, ethanol and H2 as the end metabolic products. Strains ASD3451 and ASD5720T were motile, fermented lactose and raffinose, and weakly fermented maltose. Strain ASD4241T was non-motile and did not ferment the carbohydrates listed above but fermented starch. Strains ASD3451 and ASD5720T shared average nucleotide identity higher than 98.5 % with each other, while ASD4241T had only 88.5-89 % identity to them. Based on phylogenetic and chemotaxonomic analyses, we propose Diplocloster agilis gen. nov., sp. nov. (ASD5720T=JCM 34353T=VKM B-3497T) and Diplocloster modestus sp. nov. (ASD4241T=JCM 34351T=VKM B-3498T) within the family Lachnospiraceae.

Influence of geographic conditions on body length of male newborns in Kyrgyzstan.

Newborn length has been reported by many researchers to be reduced at high altitudes. However, many of these studies lacked adequate control of the ethnic group which may be confounding the altitude differences. In addition, few studies have examined the sources of variation in birth weight at high altitudes that may be related to ethnic group adaptation to the stresses of this hypoxic environment. In our study, we tested the hypotheses that the effect of altitude differences in newborn length depends on ethnic variation. Samples of 3359 healthy male newborns from different areas in Kyrgyzstan between the years 2003 and 2011 were analyzed for altitude and ethnic variation on male newborn length. Our results indicate significant decrease in male newborn length as a latitude increase. It is concluded that ethnic group difference in pregnancy outcome reflects a better state of adaptation to high altitude in this healthy indigenous population and that long-term genetic selection may be the most plausible explanation for these ethnic differences.

Prevotella rara sp. nov., isolated from human faeces.

A strain of obligately anaerobic, Gram-stain-negative rods was isolated from human faeces and characterized both phenotypically and genotypically. Phylogenetic analysis based on 16S rRNA gene and whole-genome sequences revealed the strain to represent a member of the genus Prevotella, distant from the species with validly published names, with the closest relationship to Prevotella oryzae. The strain was moderately saccharolytic and proteolytic. The predominant menaquinones were MK-13 and MK-12. The major cellular long-chain fatty acids were anteiso-C15 : 0 and iso-C15 : 0. The genomic DNA G+C content was 45.7 mol%. On the basis of chemotaxonomic and genotypic properties, it was concluded that the strain represent a novel species within the genus Prevotella, for which the name Prevotellarara sp. nov. is proposed. The type strain of Prevotellarara is 109T (=VKM B-2992T=DSM 105141T).