Analysis of the Phospholipid Profile of the Collection Strain PAO1 and Clinical Isolates of Pseudomonas aeruginosa in Relation to Their Attachment Capacity

Bacteria form multicellular and resistant structures named biofilms. Biofilm formation starts with the attachment phase, and the molecular actors involved in this phase, except adhesins, are poorly characterized. There is growing evidence that phospholipids are more than simple structural bricks. They are involved in bacterial adaptive physiology, but little is known about their role in biofilm formation. Here, we report a mass spectrometry analysis of the phospholipid (PL) profile of several strains of Pseudomonas aeruginosa isolated from cystic fibrosis patients. The aim of our study was to evaluate a possible link between the PL profile of a strain and its attachment phenotype. Our results showed that PL profile is strongly strain-dependent. The PL profile of P. aeruginosa PAO1, a collection strain, was different from those of 10 clinical isolates characterized either by a very low or a very high attachment capacity. We observed also that the clinical strain’s PL profiles varied even more importantly between isolates. By comparing groups of strains having similar attachment capacities, we identified one PL, PE 18:1-18:1, as a potential molecular actor involved in attachment, the first step in biofilm formation. This PL represents a possible target in the fight against biofilms.

Optimization of growth processes of the selected strain Lactobacillus acidophilus (B-4107) K-1-T with the prospect of its use for the prevention of gastrointestinal diseases in calves

Gastrointestinal diseases of young cattle occupy the bulk of the total number of postnatally significant diseases in terms of coverage, which causes significant economic damage to animal husbandry. In the modern world, the basis for prophylactic that is safe for a living organism is the use of bacterial preparations created from symbiotic selected probiotic strains with the inclusion of a functional substance and a prebiotic. In this regard, the role of lactulose, which meets all the necessary international requirements, becomes particularly important. When determining the influence of the prebiotic Lactulose, as a catalytic enzyme, on the growth processes of the collection strain Lactobacillus acidophilus (B-4107) K-1-T, it was experimentally established that the prebiotic. Lactulose has a significant effect on the growth and activity of the tested strain of lactic acid microorganisms. The following data is necessary for the development of effective means of normalizing the microbiota in the prophylactic of diseases of the gastrointestinal tract of young animals of infectious and non-infectious etiology.

Isolation and study of promising strains of phosphate-mobilizing microorganisms for the creation of biofertilizer

The article describes the process of isolation and study of strains of phosphate-mobilizing microorganisms. As a result of soil analysis, the selected 9 samples contain a sufficient amount of total nitrogen, humus and mobile phosphorus compounds for the development of microorganisms. As a result of the isolation of phosphate-mobilizing microorganisms, 23 mono-isolates were selected. After incubation of the flasks, analyzes for the content of dissolved phosphorus and pH in the culture media were carried out. As a result, the highest content of dissolved phosphorus was obtained by incubation of monoisolates No. 9 and 20, which were 3.57 g/l and 2.55 g/l, respectively. Also, the pH of the medium in these monoisolates showed the lowest values: 5.4 and 5.7, respectively. Monoisolates No. 9 and 20 are named FT1 and FT2, respectively. Based on physiological and biochemical studies, isolated monoisolates were identified as Bacillus megaterium FT1 and Bacillus sp. FT2. As a result of studying phosphate-mobilizing activity in the isolated strains of soil phosphate mobilizing microorganisms and the collection strain, the new strain of B. megaterium FT1 showed the highest phosphate mobilizing activity, where 100 % of phosphorus in the medium were dissolved within 120 hours. The yield of dissolved phosphorus in the medium with the strains of Bacillus spp. FT2 and Serratia plymuthica Nl1 were 50.0 5 and 54.2 %, respectively, for 168 hours.

Microencapsulation of Saccharomyces cerevisiae into Alginate Beads: A Focus on Functional Properties of Released Cells

Five yeast strains (four wild Saccharomyces cerevisiae strains and a collection strain-S. cerevisiae var. boulardii) were encapsulated in alginate beads. Encapsulation yield was at least 60% (100% for some strains) and yeasts survived in beads for 30 days at 4 °C, although the viability was strongly affected during storage at 25 °C (3 log reduction after 7 days). The kinetic of cell release was studied under static and dynamic conditions, but the results suggest that, after 48 h, beads contained a high number of yeasts. Thus, their use is advisable as re-usable carriers of starter cultures or as a vehicle of probiotics into the gut. Finally, some functional properties (biofilm formation, hydrophobicity, auto-aggregation, survival during the transit into the gut) were evaluated on yeasts released by beads to assess if microencapsulation could negatively affect these traits. The results showed that yeasts’ entrapment in beads did not affect probiotic properties.

Complete Genome Sequence of Collection Strain Acinetobacter baumannii ATCC BAA-1790, Used as a Model To Study the Antibiotic Resistance Reversion Induced by Iodine-Containing Complexes

The strain Acinetobacter baumannii ATCC BAA-1790 was sequenced as a model for nosocomial multidrug-resistant infections. Long-read PacBio sequencing revealed a circular chromosome of 3,963,235 bp with two horizontally transferred genomic islands and a 67,023-bp plasmid. Multiple antibiotic resistance genes and genome methylation patterns were identified.

Potensi Simbiosis Cendawan Endofit pada Beberapa Tanaman Pangan dan Hortikultura

Produktivitas tanaman pangan dan hortikultura seperti kedelai, sorgum manis, cabai, dan Chinese cabbage diduga dapat ditingkatkan melalui simbiosis dengan cendawan endofit. Cendawan endofit koleksi IPB Culture Collection strain IYT30, IYT50, IYT64, IYT65, dan IYT102 belum diketahui potensi endosimbiosisnya. Oleh sebab itu penelitian ini bertujuan untuk menguji potensi simbiosis cendawan endofit tersebut terhadap tanaman pangan dan hortikultura yaitu kedelai, sorgum manis, cabai, dan Chinese cabbage pada sistem interaksi kultur aksenik. Endosimbiosis diamati dengan adanya kolonisasi cendawan endofit pada jaringan akar, serta pertumbuhan tanaman inangnya (tinggi tajuk, jumlah daun, panjang akar, dan bobot kering biomassa). Hasil penelitian menunjukkan akar kedelai dan sorgum manis tidak dapat bersimbiosis dengan cendawan endofit pada kondisi uji. Oleh sebab itu pertumbuhan tanaman lebih dipengaruhi faktor-faktor selain simbiosis. Pada akar cabai dan Chinese cabbage, kolonisasi hanya mencapai ruang antar sel jaringan korteks, kecuali pada perlakuan IYT64 pada tanaman cabai dimana kolonisasi sampai ke dalam sel. Tanaman yang diinteraksikan dengan cendawan menunjukkan respon yang tidak konsisten pada semua parameter pertumbuhan.