Methods to study microbial adhesion on abiotic surfaces

Microbial biofilms are a matrix of cells and exopolymeric substances attached to a wet and solid surface and are commonly associated to several problems, such as biofouling and corrosion in industries and infectious diseases in urinary catheters and prosthesis. However, these cells may have several benefits in distinct applications, such as wastewater treatment processes, microbial fuel cells for energy production and biosensors. As microbial adhesion is a key step on biofilm formation, it is very important to understand and characterize microbial adhesion to a surface. This study presents an overview of predictive and experimental methods used for the study of bacterial adhesion. Evaluation of surface physicochemical properties have a limited capacity in describing the complex adhesion process. Regarding the experimental methods, there is no standard method or platform available for the study of microbial adhesion and a wide variety of methods, such as colony forming units counting and microscopy techniques, can be applied for quantification and characterization of the adhesion process.This work was financially supported by: Project UID/EQU/00511/2013-LEPABE, by the FCT/MEC with national funds and co-funded by FEDER in the scope of the P2020 Partnership Agreement; Project NORTE-07-0124-FEDER-000025 - RL2_Environment&Health, by FEDER funds through Programa Operacional Factores de Competitividade-COMPETE, by the Programa Operacional do Norte (ON2) program and by national funds through FCT - Fundacao para a Ciencia e a Tecnologia; European Research Project SusClean (Contract number FP7-KBBE-2011-5, project number: 287514), Scholarships SFRH/BD/52624/2014, SFRH/BD/88799/2012 and SFRH/BD/103810/2014

Regulation and localization of amylolytic enzymes in Clostridium acetobutylicum ATCC 824.

Amylolytic activity was primarily cell associated when Clostridium acetobutylicum was grown on glucose or maltose and primarily extracellular when grown on dextrin or starch. Total amylolytic activity decreased with increasing glucose concentration. When this microorganism was grown in P2 medium containing starch, the intracellular amylolytic activity was 90% membrane bound and 10% cytoplasmic in nature. The addition of 1% glucose to 2% starch-based P2 medium at different stages of growth indicated that this carbohydrate repressed the synthesis of C. acetobutylicum amylolytic enzymes at the level of transcription

Salmonella - Distribution, Adaptation, Control Measures and Molecular Technologies

The discovery of Salmonella in swine in 1885 marked the beginning of intense efforts to control salmonellae that have continued for the past 127 years. The majority of foodborne outbreaks are caused by only a few of the 2500+ known serovars. While progress has been made on many fronts, salmonellosis has yet to be eliminated in either developed or in developing nations. This work represents the collective contributions of authors from all around the world. Chapters in this book address a wide array of topics related to understanding and controlling this pathogen, including: Salmonella as studied in the environment, air and in food products; virulence and pathogenicity; control by bacteriophages and other antimicrobials; bacterial adaptation; etc