Lipopolysaccharide (LPS, endotoxin) of Proteus bacteria-chemical structure, serological specificity and the role in pathogenicity

Lipopolysaccharides (LPS) of Gram-negative bacteria are composed of three regions: О-specific chain (OPS), the core oligosaccharide and lipid A. All three regions of Proteus LPS were studied. The differences in the structure of OPS serve as the basis for the serological classification of Proteus strains. The serological classification scheme of these bacteria currently consists of 76 serogroups. The structural diversity of the core region is characteristic for Proteus sp. and distinguishes this genus from other bacteria. In this paper the results of structural, immunochemical and serological studies of all three regions o f Proteus LPS, as well as a function of LPS as endotoxin and its role in the formation of urinary stones, swarming phenomenon and bacterial growth in biofilm are reported.Zadanie pt. „Digitalizacja i udostępnienie w Cyfrowym Repozytorium Uniwersytetu Łódzkiego kolekcji czasopism naukowych wydawanych przez Uniwersytet Łódzki” nr 885/P-DUN/2014 dofinansowane zostało ze środków MNiSW w ramach działalności upowszechniającej naukę

Modeling the Role of the Cell Cycle in Regulating Proteus mirabilis Swarm-Colony Development

We present models and computational results which indicate that the spatial and temporal regularity seen in Proteus mirabilis swarm-colony development is largely an expression of a sharp age of dedifferentiation in the cell cycle from motile swarmer cells to immotile dividing cells (also called swimmer or vegetative cells.) This contrasts strongly with reaction-diffusion models of Proteus behavior that ignore or average out the age structure of the cell population and instead use only density-dependent mechanisms. We argue the necessity of retaining the explicit age structure, and suggest experiments that may help determine the underlying mechanisms empirically. Consequently, we advocate Proteus as a model organism for a multiscale understanding of how and to what extent the life cycle of individual cells affects the macroscopic behavior of a biological system

Proteus sp. – an opportunistic bacterial pathogen – classification, swarming growth, clinical significance and virulence factors

The genus Proteus belongs to the Enterobacteriaceae family, where it is placed in the tribe Proteeae, together with the genera Morganella and Providencia. Currently, the genus Proteus consists of five species: P. mirabilis, P. vulgaris, P. penneri, P. hauseri and P. myxofaciens, as well as three unnamed Proteus genomospecies. The most defining characteristic of Proteus bacteria is a swarming phenomenon, a multicellular differentiation process of short rods to elongated swarmer cells. It allows population of bacteria to migrate on solid surface. Proteus bacteria inhabit the environment and are also present in the intestines of humans and animals. These microorganisms under favorable conditions cause a number of infections including urinary tract infections (UTIs), wound infections, meningitis in neonates or infants and rheumatoid arthritis. Therefore, Proteus is known as a bacterial opportunistic pathogen. It causes complicated UTIs with a higher frequency, compared to other uropathogens. Proteus infections are accompanied by a formation of urinary stones, containing struvite and carbonate apatite. The virulence of Proteus rods has been related to several factors including fimbriae, flagella, enzymes (urease - hydrolyzing urea to CO2 and NH3, proteases degrading antibodies, tissue matrix proteins and proteins of the complement system), iron acqusition systems and toxins: hemolysins, Proteus toxin agglutinin (Pta), as well as an endotoxin - lipopolysaccharide (LPS). Proteus rods form biofilm, particularly on the surface of urinary catheters, which can lead to serious consequences for patients. In this review we present factors involved in the regulation of swarming phenomenon, discuss the role of particular pathogenic features of Proteus spp., and characterize biofilm formation by these bacteria

PENGARUH PENGGUNAAN MEDIA SOFTWARE SIMULASI PROTEUS TERHADAP PRESTASI BELAJAR SISWA PADA MATA DIKLAT ELEKTRONIKA

Penelitian ini bertujuan untuk mengetahui perbedaan prestasi belajar siswa kelas X1 Kelas A dan Kelas B jurusan Teknik Instalasi Tenaga Listrik SMK 1 Sedayu pada mata diklat Elektronika dengan menerapkan media software simulasi proteus sebagai media pembelajaran. Metode penelitian yang digunakan adalah metode eksperimen dengan desain penelitian control group posttest only design. Sampel yang digunakan adalah kelas X1 TITL B sebagai kelompok dengan menggunakan media software simulasi proteus dan kelas XI TITL A dengan menggunakan media pembelajaran konvensional. Variabel penelitian ini adalah metode pembelajaran menggunakan media simulasi proteus (kelas eksperimen) dan penggunaan media pembelajaran konvensional (kelas kontrol) sebagai variabel bebas serta prestasi belajar sebagai variabel terikat. Metode pengumpulan data menggunakan instrumen tes. Analisis data menggunakan analisis uji beda t-test yang dikerjakan dengan bantuan software aplikasi SPSS 19. Hasil penelitian menunjukkan: 1) pengujian perbedaan rata-rata hasil belajar kelompok eksperimen dan kelompok kontrol melalui uji beda t-test adalah nilai t hitung > t tabel (3,653 > 2,001) dan nilai signifikansi 0,001 < 0,05, artinya terdapat perbedaan peningkatan prestasi belajar yang signifikan antara kelompok eksperimen dengan kelompok kontrol, 2) hasil belajar siswa dengan menggunakan media software simulasi proteus lebih tinggi dari pada hasil pembelajaran siswa dengan menggunakan media konvensional. Rata-rata hasil belajar kelompok eksperimen 75, sedangkan kelompok kontrol 66,33. Perbedaan rata-rata hasil belajar kedua kelompok tersebut mencapai 8,76 atau sebesar 13,12%. Berdasarkan kriteria ketuntasan minimal (KKM), persentase kelulusan siswa kelompok eksperimen mencapai 80% sedangkan untuk kelompok kontrol mencapai 50%. Perbedaan tingkat kelulusan kedua kelas tersebut mencapai 30%, hal ini menunjukkan pembelajaran elektronika dengan menggunakan software simulasi proteus dapat meningkatkan prestasi belajar siswa

The Proteus Navier-Stokes code

An effort is currently underway at NASA Lewis to develop two- and three-dimensional Navier-Stokes codes, called Proteus, for aerospace propulsion applications. The emphasis in the development of Proteus is not algorithm development or research on numerical methods, but rather the development of the code itself. The objective is to develop codes that are user-oriented, easily-modified, and well-documented. Well-proven, state-of-the-art solution algorithms are being used. Code readability, documentation (both internal and external), and validation are being emphasized. This paper is a status report on the Proteus development effort. The analysis and solution procedure are described briefly, and the various features in the code are summarized. The results from some of the validation cases that have been run are presented for both the two- and three-dimensional codes

Proteus: A Hierarchical Portfolio of Solvers and Transformations

In recent years, portfolio approaches to solving SAT problems and CSPs have become increasingly common. There are also a number of different encodings for representing CSPs as SAT instances. In this paper, we leverage advances in both SAT and CSP solving to present a novel hierarchical portfolio-based approach to CSP solving, which we call Proteus, that does not rely purely on CSP solvers. Instead, it may decide that it is best to encode a CSP problem instance into SAT, selecting an appropriate encoding and a corresponding SAT solver. Our experimental evaluation used an instance of Proteus that involved four CSP solvers, three SAT encodings, and six SAT solvers, evaluated on the most challenging problem instances from the CSP solver competitions, involving global and intensional constraints. We show that significant performance improvements can be achieved by Proteus obtained by exploiting alternative view-points and solvers for combinatorial problem-solving.Comment: 11th International Conference on Integration of AI and OR Techniques in Constraint Programming for Combinatorial Optimization Problems. The final publication is available at link.springer.co

On an age and spatially structured population model for Proteus Mirabilis swarm-colony development

Proteus mirabilis are bacteria that make strikingly regular spatial-temporal patterns on agar surfaces. In this paper we investigate a mathematical model that has been shown to display these structures when solved numerically. The model consists of an ordinary differential equation coupled with a partial differential equation involving a first-order hyperbolic aging term together with nonlinear degenerate diffusion. The system is shown to admit global weak solutions