Hans-Curt Flemming

Hans-Curt Flemming
University of Duisburg-Essen | uni-due · Biofilm Centre, Aquatic Microbiology

Prof. Dr.

About

274
Publications
149,872
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
25,443
Citations
Introduction
Hans-Curt Flemming, retired by the end of 2014, worked as head of the Biofilm Centre, University of Duisburg-Essen. His current project is to enjoy life: 'I am retired and happy as a pig (not a Dutch one, and not German either, but a free one). Currently, Hans-Curt Flemming is a visiting Professor at the Singapore Center for Life Sciences Engineering, still fascinated by biofilms, be it in drinking water or the environment - just the complexity of this form of microbial life.
Additional affiliations
June 2022 - May 2025
Institute of Oceanology, Chinese Academy of Sciences Qingdao
Position
  • Visiting Professor
Description
  • Lecturing, project consultation, supervision of students, public lectures
April 1996 - September 2014
University of Duisburg-Essen
Position
  • Head of Biofilm Centre
September 1994 - March 1996
Technische Universität München
Position
  • Department Leader

Publications

Publications (274)
Article
The biofilm matrix can be considered to be a shared space for the encased microbial cells, comprising a wide variety of extracellular polymeric substances (EPS), such as polysaccharides, proteins, amyloids, lipids and extracellular DNA (eDNA), as well as membrane vesicles and humic-like microbially derived refractory substances. EPS are dynamic in...
Article
Full-text available
Microorganisms are an important factor in the wash-and-use cycle of textiles since they can cause unwanted aesthetic effects, such as malodour formation, and even pose health risks. In this regard, a comprehensive view of the microbial communities in washing machines and consideration of the microbial contamination of used textiles is needed to und...
Article
Full-text available
Article
The application of membrane technology for water treatment and reuse is hampered by the development of a microbial biofilm. Biofilm growth in micro-and ultrafiltration (MF/UF) membrane modules, on both the membrane surface and feed spacer, can form a secondary membrane and exert resistance to permeation and crossflow, increasing energy demand and d...
Chapter
In the Anthropocene era, humans have become one of the most important factors influencing the Earth system. The achievements of the Anthropocene have brought us enormous prosperity. There are increasing signs that the unintended side effects are endangering this prosperity and even our civilization. The current situation, such as the separation of...
Article
Full-text available
Sessile microorganisms were described as early as the seventeenth century. However, the term biofilm arose only in the 1960s in wastewater treatment research and was adopted later in marine fouling and in medical and dental microbiology. The sessile mode of microbial life was gradually recognized to be predominant on Earth, and the term biofilm bec...
Article
Full-text available
Bacterial biofilms occur in many natural and industrial environments. Besides bacteria, biofilms comprise over 70 wt% water. Water in biofilms occurs as bound- or free-water. Bound-water is adsorbed to bacterial surfaces or biofilm (matrix) structures and possesses different Infra-red and Nuclear-Magnetic-Resonance signatures than free-water. Bound...
Chapter
Prokaryoten bauen auf unterschiedlichste Weise Biomasse auf und nutzen dazu verschiedene Energiequellen. Grundsätzlich lassen sich Ernährungstypen danach einteilen, woher die Organismen die Energie und die Elektronen für Redoxreaktionen beziehen und welche Kohlenstoffquelle sie nutzen.
Article
Full-text available
Sulfolobus acidocaldarius is a thermoacidophilic crenarchaeon with optimal growth at 80 °C and pH 2 - 3. Due to its unique physiological properties allowing life at environmental extremes and recent availability of genetic tools, this extremophile receives increasing interest for biotechnological application. In order to elucidate the potential of...
Article
Microbially influenced corrosion (MIC), is acknowledged to be the direct cause of catastrophic corrosion failures, with associated damage costs ranging to many billions of US$ annually. In spite of extensive research and numerous publications, fundamental questions relating to MIC remain unanswered. The following review provides an overview of curr...
Article
Full-text available
Tropical conditions favor the auto-decomposition of monochloramine (MCA) leading to disinfectant decay and free ammonia in drinking water distribution systems (DWDS); thus, they promote the growth of nitrifiers and the development of biofilms on the inner-pipe surface. Biofilms can adversely impact the provision of safe and biologically stable wate...
Article
Biofouling is the undesired deposition and growth of microorganisms on surfaces, forming biofilms. The definition is subjective and operational: not every biofilm causes biofouling - only if a given a subjective "threshold of interference" is exceeded, biofilms cause technical or medical problems. These range from the formation of slime layers on s...
Article
Fossilized biofilms represent one of the oldest known confirmations of life on the Earth. The success of microbes in biofilms results from properties that are inherent in the biofilm, including enhanced interaction, protection, and biodiversity. Given the diversity of microbes that live in biofilms in harsh environments on the Earth, it is logical...
Article
Biofilms are a form of collective life with emergent properties that confer many advantages on their inhabitants, and they represent a much higher level of organization than single cells do. However, to date, no global analysis on biofilm abundance exists. We offer a critical discussion of the definition of biofilms and compile current estimates of...
Article
Microbial biofilms can be both cause and cure to a range of emerging societal problems including antimicrobial tolerance, water sanitation, water scarcity and pollution. The identities of extracellular polymeric substances (EPS) responsible for the establishment and function of biofilms are poorly understood. The lack of information on the chemical...
Article
Full-text available
Biofilm formation represents a successful survival strategy for bacteria. In biofilms, cells are embedded in a matrix of extracellular polymeric substances (EPS). As they are often more stress-tolerant than single cells, biofilm cells might survive the conditions present in space and on Mars. To investigate this topic, the bacterium Deinococcus geo...
Conference Paper
In the BOSS experiment (biofilm organisms surfing space), which was performed in the context of the successfully finalized EXPOSE-R2 mission, an international consortium of scientists investigated the ability of a variety of organisms to survive in space and on Mars as a function of their life style. The question in focus is whether there are diffe...
Article
Full-text available
“Slime” played a brief and spectacular role in the 19th century founded by the theory of primordial slime by Ernst Haeckel. However, that substance was never found and eventually abandoned. Further scientific attention slowly began in the 1930s referring to slime as a microbial product and then was inspired by “How bacteria stick” by Costerton et a...
Article
Full-text available
In biofilms, the extracellular polymeric substances (EPS) provide the matrix in which the biofilm organisms are retained and develop their interactions. The properties of the EPS molecules are crucial for the living conditions of these organisms. This matrix allows for the emergence of new properties of biofilms as a whole which are not predictable...
Chapter
Full-text available
Biofilms can interfere strongly with membrane filtration performance both by increased transmembrane pressure drop and increase of feed-concentrate pressure drop. Intuitively, the transmembrane pressure drop effect seems proportional to biofilm thickness. However, only few data about the intrinsic hydraulic resistance of biofilms are available, wit...
Article
Full-text available
Bacterial biofilms are formed by communities that are embedded in a self-produced matrix of extracellular polymeric substances (EPS). Importantly, bacteria in biofilms exhibit a set of 'emergent properties' that differ substantially from free-living bacterial cells. In this Review, we consider the fundamental role of the biofilm matrix in establish...
Chapter
Full-text available
In biofilms, the extracellular polymeric substances (EPS) provide the matrix in which the biofilm organisms are retained and develop their interactions. The properties of the EPS molecules are crucial for the living conditions of these organisms. This matrix allows for the emergence of new properties of biofilms as a whole which are not predictable...
Article
For the Ruhr River, bathing has been prohibited for decades. However, along with significant improvements of the hygienic water quality, there is an increasing demand of using the river for recreational purposes, in particular for bathing. In the “Safe Ruhr” interdisciplinary research project, demands, options and chances for lifting the bathing ba...
Article
Operation of membrane systems for water treatment can be seriously hampered by biofouling. A better characterization of biofilms in membrane systems and their impact on membrane performance may help to develop effective biofouling control strategies. The objective of this study was to determine the occurrence, extent and timescale of biofilm compac...
Article
Operation of membrane systems for water treatment can be seriously hampered by biofouling. A better characterization of biofilms in membrane systems and their impact on membrane performance may help to develop effective biofouling control strategies. The objective of this study was to determine the occurrence, extent and timescale of biofilm compac...
Article
Full-text available
The antimicrobial properties of silver nanoparticles (AgNPs) have raised expectations for the protection of medical devices and consumer products against biofilms. The effect of silver on bacteria is commonly determined by culture-dependent methods. It is as yet unknown if silver-exposed bacteria can enter a metabolically active but non-culturable...
Article
Full-text available
In developing hygiene strategies, in recent years, the major focus has been on the hands as the key route of infection transmission. However, there is a multitude of lesser-known and underestimated reservoirs for microorganisms which are the triggering sources and vehicles for outbreaks or sporadic cases of infection. Among those are water reservoi...
Chapter
The biofilm mode of life is common to almost all microorganisms on Earth, be it continuously or as part of their life cycle. Biofilm phenomena are very diverse. They range from films on solid surfaces, aggregates at the water-atmosphere interface to flocs as "floating biofilms," microbial mats, and sludges as very thick biofilms. Nevertheless, they...
Article
Biofouling causes performance loss in spiral wound nanofiltration (NF) and reverse osmosis (RO) membrane operation for process and drinking water production. The development of biofilm formation, structure and detachment was studied in-situ, non-destructively with Optical Coherence Tomography (OCT) in direct relation with the hydraulic biofilm resi...
Article
Full-text available
Die Papiermaschine ist ein idealer Lebensraum für Mikroorganis-men 2,3 : sie können ihn frei über das Wasser, die Rohstoffe und die Additive erreichen und dort gibt es genügend Wasser und Nährstoffe. Die Temperaturen sind günstig (30–45 °C) und es existiert eine weite Bandbreite von Mikrohabitaten, die von total anaerob bis voll aerob reicht. 4 Das...
Article
A modified version of the membrane fouling simulator (MFS) was developed for assessment of (i) hydraulic biofilm resistance, (ii) performance parameters feed-channel pressure drop and transmembrane pressure drop, and (iii) in situ spatial visual and optical observations of the biofilm in the transparent monitor, e.g. using optical coherence tomogra...
Article
The Minimum Information About a Biofilm Experiment (MIABiE) initiative has arisen from the need to find an adequate and scientifically sound way to control the quality of the documentation accompanying the public deposition of biofilm-related data, particularly those obtained using high-throughput devices and techniques. Thereby, the MIABiE consort...
Article
The Minimum Information About a Biofilm Experiment (MIABiE) initiative has arisen from the need to find an adequate and scientifically sound way to control the quality of the documentation accompanying the public deposition of biofilm-related data, particularly those obtained using high-throughput devices and techniques. Thereby, the MIABiE consort...
Article
Biofilm formation causes performance loss in spiral-wound membrane systems. In this study a microfiltration membrane was used in experiments to simulate fouling in spiral-wound reverse osmosis (RO) and nanofiltration (NF) membrane modules without the influence of concentration polarization. The resistance of a microfiltration membrane is much lower...
Article
Full-text available
Water cooling towers are major users of water worldwide. Industrial development has resulted in an increase in the use of water for cooling tower operations. This has led to an expansion of the demand for water and natural resources, particularly in threshold countries such as China, India and South Africa. It is well known that how we use water in...
Article
Full-text available
As an opportunistic human pathogen Pseudomonas aeruginosa is able to cause acute and chronic infections. The biofilm mode of life significantly contributes to the growth and persistence of P. aeruginosa during an infection process and mediates the pathogenicity of the bacterium. Within a biofilm mucoid strains of P. aeruginosa simultaneously produc...
Article
Full-text available
Paper mills are open systems, which provide favorable conditions for microbial growth. Microbial contamination can cause substantial economic losses, including the deterioration of raw materials, interference with production processes by breakdowns and lowering product quality, and eventually, problems in wastewater treatment. Damage is caused by a...
Article
Based on the latest knowledge about microorganisms resistant towards extreme conditions on Earth and results of new complex models on the development of the Martian atmosphere we quantitatively examined the water-bearing properties of selected extremophiles and simulated Martian regolith components and their interaction with water vapor under close...
Chapter
Full-text available
Sentinel coupon devices may be installed in water distribution systems for decontamination surveillance. They give the possibility to extract samples and perform off-line laboratory analysis. The objective of this research work is to develop a concept for positioning sentinel coupons and sensors at representative and indicative locations in the wat...
Article
Full-text available
Deposits on surfaces in water-bearing systems, also known as 'fouling', can lead to substantial losses in the performance of industrial processes as well as a decreased product quality. Early detection and localization of such deposits can, to a considerable extent, save such losses. However, most of the surfaces that become fouled, for example, in...
Article
a b s t r a c t Biofilms may interfere with membrane performance in at least three ways: (i) increase of the transmembrane pressure drop, (ii) increase of feed channel (feed-concentrate) pressure drop, and (iii) increase of transmembrane passage. Given the relevance of biofouling, it is surprising how few data exist about the hydraulic resistance o...
Article
The question of life on Mars has been in focus of astrobiological research for several decades, and recent missions in orbit or on the surface of the planet are constantly expanding our knowledge on Martian geochemistry. For example, massive stratified deposits have been identified on Mars containing sulfate minerals and iron oxides, which suggest...
Chapter
In water distribution systems, surface deposits can act as sink and source for contaminants. To gain information about presence and amount of deposits as well as of the success of deposit removal after performing a cleaning procedure the systematic deposition of online deposit sensors or coupon sampling devices is important. In order to address thi...
Article
Microbial biofilms show properties not predictable from those of single cells, e.g., the formation of a matrix of extracellular polymeric substances (EPS) with high cell densities, intense intercellular communication, concentration gradients, and structural heterogeneity. The result: a wide variety of habitats and the formation of multispecies micr...
Article
In the experiment BOSS the hypothesis will be tested if the biofilm form of life with microorganisms embedded and aggregated in their EPS matrix is suited to support long-term survival of microorganisms under the harsh environmental conditions as they exist in space and on Mars and is superior to the same bacteria in the form of planktonic cultures...
Conference Paper
Full-text available
Introduction Biofouling of membranes is caused by biofilms. The biofilm acts as a secondary membrane on top of the filtration membrane, influencing the overall membrane resistance. In this study, the contribution of the biofilm should be determined. In order to do so, a microfiltration membrane was chosen because its intrinsic resistance is expec...
Article
Full-text available
Reg Bott is a long standing member of my hall of fame, and in this text he discusses the challenges and benefits of biofilms on industrial surfaces
Article
The biofilm mode of life is only possible because biofilm organisms are transiently immobilized in a matrix of extracellular polymeric substances (EPS), also known as "slime". The matrix can be considered an emerging property of microorganisms, allowing them to form stable synergistic consortia, supporting interaction by signaling molecules and hor...
Article
Copper plumbing materials can be the source of copper ions in drinking water supplies. The aim of the current study was to investigate the influence of copper ions on the viability and cytotoxicity of the potential pathogen Pseudomonas aeruginosa that presents a health hazard when occurring in building plumbing systems. In batch experiments, exposu...
Chapter
Full-text available
Microbial biofouling is a very costly problem, keeping busy a billion dollar industry providing biocides, cleaners, and antifouling materials worldwide. Basically, five general reasons can be identified, which continuously compromise the efficacy of antifouling strategies:1. Biofouling is detected by its effect on process performance or product qua...
Article
Most microorganisms on Earth live in various aggregates which are generally termed "biofilms". They are ubiquitous and represent the most successful form of life. They are the active agent in biofiltration and the carriers of the self-cleaning potential in soils, sediments and water. They are also common on surfaces in technical systems where they...
Article
Full-text available
Book
Living in biofilms is the common way of life of microorganisms, transiently immobilized in their matrix of extracellular polymeric substances (EPS), interacting in many ways and using the matrix as an external digestion and protection system. This is how they have organized their life in the environment, in the medical context and in technical syst...
Article
Full-text available
The ability of certain microbial species to survive adverse conditions such as radiation and desiccation has been an important research subject for astrobiology. The reason for this is perhaps the traditional view that life at the surface of planets, which generally have thin atmospheres, low amounts of water and intense radiation, might be possibl...
Article
Although synthetic polymers are part of our global waste problem because they are not sufficiently biologically degraded, microorganisms can severely impair the properties and functions of these materials. It seems as if consumers do not really acknowledge this cause of problems and there is only sparse systematic research about. Damaging mechanism...
Article
Full-text available
Article
Full-text available
The microorganisms in biofilms live in a self-produced matrix of hydrated extracellular polymeric substances (EPS) that form their immediate environment. EPS are mainly polysaccharides, proteins, nucleic acids and lipids; they provide the mechanical stability of biofilms, mediate their adhesion to surfaces and form a cohesive, three-dimensional pol...
Article
Drinking water biofilms were grown on coupons of plumbing materials, including ethylene-propylene-diene-monomer (EPDM) rubber, silane cross-linked polyethylene (PE-X b), electron-ray cross-linked PE (PE-X c) and copper under constant flow-through of cold tap water. After 14 days, the biofilms were spiked with Pseudomonas aeruginosa, Legionella pneu...