[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$fxLN3MUwXCdr5RPjwZYIDpOj8CHyjOmngWTgoKXPtZbg":3,"$fQlZj21QwvEphK5OqlZNbPufPX7yVCzOnj3uZYvg_RWw":32,"$f3Ft0rKFJHppdzE-vuveecxx1BUcg9iOlMLtyzf_MJDg":47},[4,8,12,16,20,24,28],{"title":5,"slug":6,"path":7},"About Microbeonline.com","about-microbeonline-com","\u002Fabout-microbeonline-com\u002F",{"title":9,"slug":10,"path":11},"About Me","about-me","\u002Fabout-microbeonline-com\u002Fabout-me\u002F",{"title":13,"slug":14,"path":15},"Advertise with Us","advertise-us","\u002Fadvertise-us\u002F",{"title":17,"slug":18,"path":19},"Privacy Policy","privacy-policy","\u002Fprivacy-policy\u002F",{"title":21,"slug":22,"path":23},"Abbreviations","abbreviations","\u002Fabbreviations\u002F",{"title":25,"slug":26,"path":27},"Microbes","microbes","\u002Fmicrobes\u002F",{"title":29,"slug":30,"path":31},"Books","recommended-books","\u002Frecommended-books\u002F",{"type":33,"data":34},"blog",{"slug":35,"title":36,"description":36,"seoTitle":37,"seoDescription":37,"author":38,"createdDate":39,"lastUpdatedDate":40,"draft":41,"category":42,"image":37,"body":43,"faq":44,"tags":45,"related":46},"proteus-species-properties-diseases-identification","Proteus species: Properties, Diseases, Identification",null,"Acharya Tankeshwar","2019-03-18","2025-12-29",false,"bacteriology","*Proteus* are Gram-negative rod-shaped bacteria of the family \\*Enterobacteriaceae.\\*They are widely distributed in nature and also occur as normal intestinal flora of humans. An opportunistic pathogen, they are one of the common causes of [urinary tract infections (UTIs) ](\u002Fmicrobial-etiology-urinary-tract-infections-uti\u002F)and are associated with infection-induced renal stones. Other infections caused by *Proteus* species are pyogenic lesions, infections of the ear, respiratory tract infections, and nosocomial infections.\n\n*Proteus* species have [pili (fimbriae)](\u002Fbacterial-pili-fimbriae-characteristics-types-and-medical-importance\u002F). Pili are associated with adhesive properties and, in some cases, are correlated with virulence.\n\n> The word ‘Proteus’ was derived from Greek mythology, which described ‘Proteus’ as an early sea-god, noted for being versatile and capable of assuming many different forms. Plemorphic nature of this organism and its rapid swarming motility might have persuaded its discoverer Gustav Hauser to rename it as Proteus.\n\n## Characteristics of Proteus spp\n\n1. Gram-negative\n2. Non-spore-forming rods\n3. Facultative anaerobes\n4. Urease positive (strong)\n5. Oxidase test: Negative\n6. Nitrates are reduced to nitrites\n7. Ferments glucose but does not ferment lactose\n8. Deaminates phenylalanine to phenyl pyruvic acid\n\n[Urease enzyme](\u002Furease-test-principle-procedure-interpretation-and-urease-positive-organsims\u002F) produced by *Proteus* species is thought to play a major role in the production of infection-induced urinary stones. The ammonia produced after the breakdown of the urea results in struvite (magnesium ammonium phosphate) stone formation. Recurrent urinary tract infections with a urease-producing organism (mostly I species) result in the formation of **staghorn calculi** in the kidney.\n\n![ - Stag (male deer) and Staghorn calculi (source)](https:\u002F\u002Fassets.microbeonline.com\u002Fblogs\u002FStag-Horn-and-Stag-horn-renal-calculi.png)Figure: Stag (male deer) and Staghorn calculi (source)\n\n### Antigenic characteristics\n\nThe bacilli possess thermostable, ‘O’ (somatic) and thermostable ‘H’ (flagellar) antigens, based upon which several serotypes have been recognized.\n\nCertain strains of *Pvulgaris* (OX-19, OX-2, and OX-K) produce O antigens that some rickettsiae share. These *Proteus* strains are used in an agglutination test (the **Weil-Felix test**) for serum antibodies produced against rickettsiae of the typhus and spotted fever groups.\n\n### Biochemical Properties of *Proteus mirabilis* and *Proteus vulgaris*\n\nOrganisms that swarm on 5% sheep **blood agar**, exhibit a [characteristic odor](\u002Fpathogenic-microbes-characteristics-smell-good-bad\u002F), and are oxidase negative can be presumptively identified as *Proteus spp*.  With further testing by spot indole, the positive isolates may be presumptively reported as *Proteus vulgaris* and the negative ones as *Proteus mirabilis.*\n\n| Properties | Proteus mirabilis | Proteus vulgaris |\n| --- | --- | --- |\n| Colony characteristics in MacConkey Agar | Pale or colourless (NLF) colonies | Pale or colourless (NLF) colonies |\n| Motility | Swarming motility | Swarming motility |\n| Lactose fermentation | No | No |\n| Indole production | No | Yes |\n| Urease production | Yes | Yes |\n| H 2 S production | Yes | Yes |\n\n## Laboratory Diagnosis & Identification\n\nThe sample used for the isolation and identification of the *Proteus* species depends on the nature of the disease\u002Fsite of infections. For UTI, a midstream urine sample is used, and for pyogenic lesions, it is the pus aspirate. The sample should be collected in a sterile container maintaining aseptic conditions and reach the laboratory within an hour of collection.\n\n**Culture:** The choice of the culture media used to isolate the etiological agents depends on the nature of the specimen and suspected pathogens. For pus & urine samples, blood agar and MacConkey agar are commonly used. Proteus grows on the Blood agar plate in successive waves to form a thin filmy layer of concentric circles ( swarming). Proteus does not swarm in the [MacConkey agar medium](\u002Fmacconkey-agar-mac-composition-preparation-uses-and-colony-characteristics\u002F) and forms smooth, pale or colorless (NLF) colonies.\n\n![ - Swarming in Blood Agar (Source)](https:\u002F\u002Fassets.microbeonline.com\u002Fblogs\u002FProteus-mirabilis-in-blood-agar.jpg)Figure: Swarming in Blood Agar (Source)\n\nSwarming properties of *Proteus* present problems in the diagnostic laboratory when mixed growth is present in which *Proteus* is one of the isolate. Several methods have been used to inhibit swarming. These are\n\n- increase in agar concentration in the medium, raising it to 6% instead of 1-2%.\n- incorporation of chloral hydrate (1:500), sodium azide (1:500), and boric acid (1:1000) in the medium\n- Using [cysteine lactose electrolyte deficient (CLED) agar](\u002Fcled-agar-composition-uses-typical-colony-characteristics\u002F) as a sole medium instead of MacConkey agar and blood agar to process urine samples.\n\n#### Dienes Phenomenon\n\n*Proteus mirabilis* is well known for its ability to differentiate into hyperflagellated, motile, and elongated swarmer cells rapidly spreading over a surface.\n\nWhen two different strains of *P. mirabilis* swarm on the same agar plate, a visible demarcation line with lower cell density forms at the intersection, and this line is known as a Dienes line \\*(after Louis Dienes, who described the phenomenon in 1946) **BUT** when two identical isolates meet, the swarming edges merge without formation of a **Dienes line**.\n\nThis phenomenon is of value in differentiating the two strains of Proteus for epidemiological purposes. Find more about Dienes phenomenon in “[small things considered blog](https:\u002F\u002Fschaechter.asmblog.org\u002Fschaechter\u002F2011\u002F11\u002Fare-you-me-or-am-i-you.html).”\n\n#### Identification\n\nGram staining, colony characteristics in culture media, and above mentioned biochemical tests (indole production, urease production, H2S production, and more importantly, phenyl pyruvic acid (PPA),etc. ) when used in combination are sufficient to identify an isolate as *Proteus* species.\n\n**References**\n\n1. Madigan Michael T, Bender, Kelly S, Buckley, Daniel H, Sattley, W. Matthew, & Stahl, David A. (2018). [Brock Biology of Microorganisms](https:\u002F\u002Famzn.to\u002F2USOj0v) (15th Edition). Pearson.\n2. [Bailey & Scott’s Diagnostic Microbiology](https:\u002F\u002Famzn.to\u002F2WZxPHL), Forbes, 11th edition",[],[],[],[48,54,61,66,70,74,79,84,88,92],{"slug":49,"name":38,"description":50,"image":51,"body":52,"postCount":53},"acharya-tankeshwar","Editor-in-chief","https:\u002F\u002Fassets.microbeonline.com\u002Fauthors\u002Ftankeshwar-acharya-author-microbeonline.jpg","***Tankeshwar Acharya, MSc (Medical Microbiology)***\n\n*Tankeshwar Acharya is an Assistant Professor in the Department of Microbiology at Patan Academy of Health Sciences (PAHS), Nepal, where he has been teaching and practicing clinical microbiology for over 14 years. He is the founder of Microbe Online, one of the leading free microbiology education resources on the web, covering bacteriology, mycology, parasitology, immunology, and clinical laboratory diagnostics written from direct experience in both the classroom and the diagnostic laboratory.*",433,{"slug":55,"name":56,"description":57,"image":58,"body":59,"postCount":60},"ashma-shrestha","Ashma Shrestha","SEO Copywriter and Science Communicator\nKathmandu, Nepal","https:\u002F\u002Fassets.microbeonline.com\u002Fauthors\u002Fashma-shrestha.png","Ashma Shrestha holds a Master of Science in Medical Microbiology from the Institute of Science and Technology (IOST), Tribhuvan University, Nepal, where she developed a strong foundation in virology, molecular biology, and diagnostic microbiology.\n\nShe now works as an SEO Copywriter at Resolution Digital, where she combines her scientific training with research-driven content strategy. She is certified in Google Analytics and Google Business Profile (GBP), and brings a data-informed approach to science communication writing content that is not only accurate but structured to reach and serve the students who need it most.\n\nAt microbeonline, Ashma contributes articles primarily in virology and molecular biology, areas she finds most compelling for their mechanistic depth and their growing clinical relevance. Her writing reflects the same standard the site is built on: factual rigor, clear explanation of the *why* behind microbiology concepts, and content that helps students move from memorization to genuine understanding.\n\nShe is passionate about making complex microbiological concepts accessible without sacrificing accuracy; a skill that sits at the intersection of her scientific training and her professional work in content and SEO.",81,{"slug":62,"name":63,"description":64,"image":37,"body":37,"postCount":65},"sushmita-baniya","Sushmita Baniya","Author \u002F Contributor",32,{"slug":67,"name":68,"description":64,"image":37,"body":37,"postCount":69},"samikshya-acharya","Samikshya Acharya",20,{"slug":71,"name":72,"description":64,"image":37,"body":37,"postCount":73},"alisha-tripathi","Alisha Tripathi",6,{"slug":75,"name":76,"description":77,"image":37,"body":37,"postCount":78},"aastha-shrestha","Aastha Shrestha"," Author \u002F Contributor",10,{"slug":80,"name":81,"description":82,"image":37,"body":37,"postCount":83},"guest-author","Guest Author","Guest Author \u002F Contributor",2,{"slug":85,"name":86,"description":64,"image":37,"body":37,"postCount":87},"srijana-khanal","Srijana Khanal",18,{"slug":89,"name":90,"description":82,"image":37,"body":37,"postCount":91},"dr-poonam-acharya","Dr. Poonam Acharya",1,{"slug":93,"name":94,"description":64,"image":37,"body":95,"postCount":96},"nisha-rijal","Nisha Rijal","**Nisha Rijal** is a microbiologist and quality assurance specialist. She served for nearly 12 years as a microbiologist at the National Public Health Laboratory (NPHL), Nepal's national reference laboratory, and continues to work as a consultant microbiologist in international public health organization. ",51]