All posts by Postępy Mikrobiologii

ROLA PROTEAZY ASPARTYLOWEJ W WIRULENCJI CANDIDA ALBICANS CZĘŚĆ II: EKSPRESJA SAP1-10 PROTEAZY ASPARTYLOWEJ PODCZAS ZAKAŻEŃ CANDIDA ALBICANS IN VIVO

ROLE OF ASPARTIC PROTEINASES IN CANDIDA ALBICANS VIRULENCE. PART II: EXPRESSION OF SAP1-10 ASPARTIC PROTEINASE DURING CANDIDA ALBICANS INFECTIONS IN VIVO
M. Staniszewska, M. Bondaryk, K. Siennicka, J. Piłat, M. Schaller, W. Kurzątkowski

1. Ekspresja genów proteazy aspartylowej podczas zakażeń Candida albicans in vivo. 2. Ekspresja genów proteazy aspartylowej u innych gatunków z rodzaju Candida. 3. Inhibitory proteazy aspartylowej. 4. Podsumowanie

Abstract: Candida albicans is an opportunistic fungal pathogen known to produce several secreted hydrolytic enzymes, among which aspartic proteinases are considered to be a key virulence factor in pathogenesis. During last decade, Saps have been extensively studied in several in vivo studies based on human samples and animal models. It has been demonstrated that SAP5 and SAP9 are the most highly expressed proteinase genes in vivo. Despite many studies, very little is known about SAP7 and SAP8 role in C. albicans pathogenesis. Moreover, this review presents Sap regulation by nutritional supplementation and environmental factors, i.e. temperature, pH and the growth phase of C. albicans cells. In addition, Saps presence is discussed in Candida tropicalis as well as Candida parapsilosis and Candida guilliermondii as contribution of these non-albicans Candida strains in clinical infections is gradually increasing. Furthermore, the review underscores the need for studies using Sap enzymes as a potential drug-target due to their key role in virulence of Candida spp. The studies using the classical aspartic PI pepstatin A and HIV PIs provided evidence for the contribution of Sap to C. albicans virulence. Therefore, more conclusive studies concerning the 10 SAP gene expression and their regulation during infective process, association of Saps production with other virulence processes of C. albicans and Saps immune response in animal and human infection still have to be conducted.

1. Aspartic proteinase genes expression during Candida albicans infections in vivo. 2. Other non-albicans species that produce aspartic proteinases. 3. Aspartic proteinase inhibitors 4. Summary

WSPÓŁZALEŻNOŚCI MIĘDZY FLORĄ JELITOWĄ I PASOŻYTAMI GRYZONI

Interactions between intestinal micro!ora and parasites of rodents
Karolina Kowalkowska, Anna Okulewicz

1. Wprowadzenie. 2. Jelitowa flora bakteryjna gryzoni. 3. Badania na zwierzętach doświadczalnych. 4.Podsumowanie

Abstract: Natural intestinal microfora is a complex system of microorganisms providing homeostasis in the gastrointestinal tract of the host. Next to the bacterial commensals, there are other, larger and more hostile to the host organisms such as parasites. Laboratory rodent (mice and rats) may be contaminated with intestinal parasites, mainly pinworm species. Helminth parasites can alter the interpretation of final results. It is known that intestinal flora and parasites of animals may interact with each-other, but the nature of those relationships is not fully investigated. Unfortunately, our state of knowledge does not allow to predict the direction of those interactions, hence it seems important to carry out further research on this issue. In this work, current results of experimental studies on interactions between intestinal microfora and parasites of rodents are presented.

1. Introduction. 2. Intestinal bacterial flora of rodents. 3. Studies in experimental animals. 4. Summary

CHLAMYDIE ŚRODOWISKOWE – NOWE DANE

Environmental chlamydiae – new data
Małgorzata Pawlikowska, Wiesław Deptuła

1. Wprowadzenie. 2. Charakterystyka rodziny Parachlamydiaceae. 3. Charakterystyka rodziny Simkaniaceae. 4. Charakterystyka rodziny Rhabdochlamydiaceae. 5. Charakterystyka rodziny Waddliaceae. 6. Charakterystyka rodziny Piscichlamydiaceae. 7. Charakterystyka rodziny Clavochlamydiaceae. 8. Charakterystyka rodziny Criblamydiaceae. 9. Charakterystyka chlamydii niesklasyfikowanych. 10. Podsumowanie

Abstract: To date, studies concerning bacteria from the order  were focused on a pathogen belonging to Chlamydiaceae family. Lately, thanks to molecular biology techniques, the taxonomy of Chlamydiales was expanded with four new families: Rhabdochlamydiaceae, Piscichlamydiaceae, Clavochlamydiaceae and Criblamydiaceae and new isolates non-classified to any family. Tese bacteria are isolated as endosymbionts of insects, fishes and from water and water desposits. Among these microorganisms, environmental chlamydiae have been identified, as pathogens of human and animals.

1. Introduction. 2. Characteristics of Parachlamydiaceae family. 3. Characteristics of Simkaniaceae family. 4. Characteristics of Rhabdochlamydiaceae family. 5. Characteristics of Waddliaceae family. 6. Characteristics of Piscichlamydiaceae family. 7. Characteristics of Clavochlamydiaceae family. 8. Characteristics of Criblamydiaceae family. 9. Characteristics of non-classified chlamydiae. 10. Summary

MECHANIZMY WIRULENCJI STREPTOCOCCUS PYOGENES

Patogenicity mechanisms of Streptococcus pyogenes
K. Szczypa, J. Wilemska, W. Hryniewicz, I. Sitkiewicz

1. Wstęp. 2. Charakterystyka zakażeń powodowanych przez S. pyogenes. 3. Czynniki wirulencji S. pyogenes. 3.1. Adhezyny. 3.2. Czynniki sprzyjające rozprzestrzenianiu się infekcji w organizmie gospodarza. 3.3. Toksyny. 4. Regulacja ekspresji czynników wirulencji. 5. Podsumowanie

1. Introduction. 2. Infections caused by S. pyogenes. 3. Virulence factors of S. pyogenes. 3.1. Adhesins. 3.2. Factors of infections in host organism. 3.3. Toxins. 4. Regulation of virulence factors expression. 5. Summary

Abstract: The group A Streptococcus (Streptococcus pyogenes, GAS) is responsible for over 600 million infections and over half million deaths a year. GAS is a major human pathogen which causes diseases ranging from mild superficial infections of the throat or skin, up to severe systemic and invasive diseases such as necrotizing fasciitis and streptococcal toxic shock syndrome. Nowadays, post-infection sequelae such as glomerulonephritis and rheumatic fever are also alarming medical problems worldwide. Molecular analyses of streptococcal virulence carried by multiple centers worldwide, suggest the presence of a complex mechanism that coordinates pathogenesis. It involves a broad range of unique protein virulence factors, as M protein, superantigens, proteases and DNases, affecting tissues and the host’s immune system. Detailed analyses of individual virulence factors as well as regulatory systems that coordinate expression of virulence factors are the first steps on the way to develop innovative strategies for diagnostics and treatment. This review aims to highlight the epidemiology of S. pyogenes and summarize the current state of knowledge about the mechanisms of its virulence.

CLOSTRIDIUM PERFRINGENS JAKO CZYNNIK ETIOLOGICZNY BIEGUNKI POANTYBIOTYKOWEJ

Clostridium perfringens as the etiological agent of antibiotic associated diarrhoea
J. Kądzielska, P. Obuch-Woszczatyński, H. Pituch, G. Młynarczyk

1. Wstęp. 2. Enterotoksyna Clostridium perfringens (CPE). 2.1. Budowa enterotoksyny. 2.2. Molekularne podstawy toksynotwórczości szczepów C. perfringens typu A. 2.3. Mechanizm działania enterotoksyny C. perfringens (CPE). 3. Sporulacja C. perfringens. 4. Biegunka poantybiotykowa o etiologii C. perfringens. 5. Diagnostyka biegunki o etiologii C. perfringens typu A. 6. Nowe czynniki zjadliwości C. perfringens typu A. 7. Podsumowanie

Abstract: Clostridium perfringens strains are classified into one of five types (A-E) based on their ability to produce four major toxins: α, β, ε, ι. C. perfringens strains belonging to biotype A may cause gas gangrene and different gastrointestinal infections such as antibioticassociated diarrhoea (AAD), sporadic diarrhoea (SD), necrotizing enterocolitis and food poisoning. The major role in the pathogenesisof C. perfringens diarrhoea plays the enterotoxin (CPE). Presented review describes structure, mechanism of action and molecular background of C. perfringens enterotoxin (CPE). Mechanism of C. perfringens type A sporulation and its importance in causing case of diarrhoea is described. In addition literature reports of cases of AAD and sporadic diarrhoea, risk groups and available diagnostic methods are discussed. Special attention is paid to new virulence factors produced by C. perfringens such as beta2 toxin (β2), isolated from AAD cases, and its possible inffuence on clinical picture of the disease.

1. Introduction. 2. Clostridium perfringens enterotoxin (CPE). 2.1. Structure of enterotoxin. 2.2. Molecular background of toxicity of C. perfringens type A strains. 2.3. Mechanism of action of C. perfringens enterotoxin (CPE). 3. Sporulation of C. perfringens. 4. Antibioticassociated diarrhoea caused by C. perfringens. 5. Diagnosis of diarrhoea caused by C. perfringens type A. 6. New virulence factors of C. perfringens type A. 7. Summary

Najnowszy numer

Najnowszy numer

POSTĘPY MIKROBIOLOGII
2018, 57, 1

O Towarzystwie

PTM

Celem Polskiego Towarzystwa
Mikrobiologów jest propagowanie rozwoju nauk mikrobiologicznych

i popularyzowanie osiągnięć
mikrobiologii wśród członków Towarzystwa oraz szerokich kręgów społeczeństwa. Formami działalności jest organizowanie zjazdów, posiedzeń naukowych, kursów, wykładów
i odczytów oraz konkursów prac naukowych; wydawanie i popieranie wydawania czasopism naukowych, książek
i innych publikacji
z dziedziny mikrobiologii; opiniowanie o stanie i potrzebach mikrobiologii polskiej

i występowanie w jej sprawach wobec
władz państwowych; współpraca
z pokrewnymi stowarzyszeniami
w kraju i za granicą.