Morphometric variability among genetically and hydrologically isolated populations can be quite high. anguinus has a shorter trunk, but a proportionately longer tail and extremities. Cervical vertebrae are often elongated as well. anguinus are elongated and flattened, and the cranial bones are longer and the teeth more numerous than in the pigmented form. The skin is thinner than in the pigmented form, and contains fewer multicellular glands. Melanin synthesis can be light-induced, and after a prolonged exposure to light, the animals turn dark. In contrast, the widespread, troglomorphic Proteus anguinus anguinus is characterized by a yellowish to pinkish-white skin, with few scattered melanophores (pigment cells) invisible to the naked eye ( Fig. Conversely, the pineal gland, which in amphibians controls circadian rhythms, gamete development, and pigmentation changes, is greatly reduced. Its small but functional eyes are covered with a transparent skin and have well-differentiated lens and retina. Despite having an entirely subterranean life, this salamander is darkly pigmented ( Fig. Morphologically, the extremely rare subspecies Proteus anguinus parkelj, found only in the springs of two streams near Jelševnik in Bela Krajina (southeastern Slovenia), is believed to resemble the supposed epigean ancestor of both forms. Conversely, it has been hypothesized that troglomorphism might have evolved in less than 500,000 years (Trontelj et al., 2007). These are about 5 to about 15 million years old, that is, they originated in the Pliocene or Miocene. anguinus is divided into six divergent lineages. anguinus may be a complex of several species that independently evolved troglomorphic traits. Analyses of molecular data suggest, however, that P. ![]() The species is currently divided into two subspecies based on the extent of troglomorphism. (C) Female protecting her clutch of eggs from predation by conspecifics. This unique population was discovered toward the end of the twentieth century. (B) A rare, pigmented individual with eyes, from southeastern Slovenia. Its earliest representation may be a Venetian stone carving from the tenth or eleventh century. (A) Described in 1768, this blind salamander was the first scientifically documented cave-dwelling animal, but its existence had already been known long before. Not all Providencia strains have urease activity.įigure 1. ( Providencia alcalifaciens, Providencia heimbachae, Providencia stuartii, Providencia rettgeri, and Providencia rustigianii) have the phenylalanine-deaminating activity that Proteus spp. Another genus in the tribe Proteeae is the genus Providencia. morganii is divided into two subspecies, M. The genus Morganella includes only one species, Morganella morganii, which was formerly Proteus morganii. The tribe Proteeae comprises three genera, Proteus, Providencia, and Morganella. Proteus myxofaciens, isolated from the larvae of gypsy moths, is not considered to be an important species causing human infections. penneri infection in humans, which is mostly nosocomial infection. Proteus mirabilis is the dominant Proteus spp. The three genomospecies left unnamed are due to the lack of phenotypical discrimination standards. Proteus hauseri and the three unnamed species were characterized as four new genomospecies from a biogroup that was considered as P. Besides these, there are three unnamed Proteus genomospecies. The genus Proteus belongs to the tribe Proteeae of family Enterobacteriaceae and includes five species: Proteus vulgaris, Proteus mirabilis, Proteus penneri, Proteus myxofaciens, and Proteus hauseri. They also oxidatively deaminate amino acids, hydrolyze urea, exhibit proteolytic activity, and produce hemagglutinins and hemolysins. The optimal temperature for Proteus is 25 ☌. Proteus strains are able to grow in temperatures ranging from 10 to 43 ☌. When Proteus grows in milk, the milk curds, and then liquefies. do not form spores, and they can grow on most culture media and liquefied gelatin. In autumn, the rate of Proteus detection is higher. ![]() indicates that affected food is not prepared in hygienic surroundings. Proteus causes food spoilage of raw meat, seafood, vegetables, and canned food. As an opportunistic human pathogen, Proteus is found in the human and animal gastrointestinal tract, skin, and oral mucosa, as well as in feces, soil, water, and plant. The Proteus habitat is widely distributed in the environment. Some characteristics of a Proteus culture are swarming and an ammonia smell. With peritrichouse flagella, Proteus spp. They are named based on their ability to undergo morphological changes of colonies. Their size is 0.4–0.8 μm in diameter and 1.0–3.0 μm in length. Yong Wang, Xiaoling Pan, in Encyclopedia of Food Safety, 2014 Background
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