Lysis in the context of "Lambda phage"

Gram-negative bacteria are bacteria that, unlike Gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists of a thin peptidoglycan cell wall sandwiched between an inner (cytoplasmic) membrane and an outer membrane. These bacteria are found in all environments that support life on Earth.

Within this category, notable species include the model organism Escherichia coli, along with various pathogenic bacteria, such as Pseudomonas aeruginosa, Chlamydia trachomatis, and Yersinia pestis. They pose significant challenges in the medical field due to their outer membrane, which acts as a protective barrier against numerous antibiotics (including penicillin), detergents that would normally damage the inner cell membrane, and the antimicrobial enzyme lysozyme produced by animals as part of their innate immune system. Furthermore, the outer leaflet of this membrane contains a complex lipopolysaccharide (LPS) whose lipid A component can trigger a toxic reaction when the bacteria are lysed by immune cells. This reaction may lead to septic shock, resulting in low blood pressure, respiratory failure, reduced oxygen delivery, and lactic acidosis.

Pyrolysis (/paɪˈrɒlɪsɪs/; from Ancient Greek πῦρ pûr 'fire' and λύσις lýsis 'separation') is a process involving the separation of covalent bonds in organic matter by thermal decomposition within an inert environment without oxygen.

Saprotrophic nutrition /sæprəˈtrɒfɪk, -proʊ-/ or lysotrophic nutrition is a process of chemoheterotrophic extracellular digestion involved in the processing of decayed (dead or waste) organic matter. It occurs in saprotrophs (organisms which feed on decaying organic matter), and is most often associated with fungi (e.g. Mucor) and with soil bacteria. Saprotrophic microscopic fungi are sometimes called saprobes. Saprotrophic plants or bacterial flora are called saprophytes (sapro- 'rotten material' + -phyte 'plant'), although it is now believed that all plants previously thought to be saprotrophic are in fact parasites of microscopic fungi or of other plants. In fungi, the saprotrophic process is most often facilitated through the active transport of such materials through endocytosis within the internal mycelium and its constituent hyphae.

Various word roots relating to decayed matter (detritus, sapro-, lyso-), to eating and nutrition (-vore, -phage, -troph), and to plants or life forms (-phyte, -obe) produce various terms, such as detritivore, detritophage, saprotroph, saprophyte, saprophage, and saprobe; their meanings overlap, although technical distinctions (based on physiologic mechanisms) narrow the senses. For example, biologists can make usage distinctions based on macroscopic swallowing of detritus (as in earthworms) versus microscopic lysis of detritus (as with mushrooms).

An exotoxin is a toxin secreted by bacteria. An exotoxin can cause damage to the host by destroying cells or disrupting normal cellular metabolism. They are highly potent and can cause major damage to the host. Exotoxins may be secreted, or, similar to endotoxins, may be released during lysis of the cell. Gram negative pathogens may secrete outer membrane vesicles containing lipopolysaccharide endotoxin and some virulence proteins in the bounding membrane along with some other toxins as intra-vesicular contents, thus adding a previously unforeseen dimension to the well-known eukaryote process of membrane vesicle trafficking, which is quite active at the host–pathogen interface.

They may exert their effect locally or produce systemic effects. Well-known exotoxins include: botulinum toxin produced by Clostridium botulinum; Corynebacterium diphtheriae toxin, produced during life-threatening symptoms of diphtheria; tetanospasmin produced by Clostridium tetani. The toxic properties of most exotoxins can be inactivated by heat or chemical treatment to produce a toxoid. These retain their antigenic specificity and can be used to produce antitoxins and, in the case of diphtheria and tetanus toxoids, are used as vaccines.

Hemolysis or haemolysis (/hiːˈmɒlɪsɪs/), also known by several other names, is the rupturing (lysis) of red blood cells (erythrocytes) and the release of their contents (cytoplasm) into surrounding fluid (e.g. blood plasma). Hemolysis may occur in vivo or in vitro.

One cause of hemolysis is the action of hemolysins, toxins that are produced by certain pathogenic bacteria or fungi. Another cause is intense physical exercise. Hemolysins damage the red blood cell's cytoplasmic membrane, causing lysis and eventually cell death.