Treponema pallidum: Difference between revisions

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{{subpages}}{{CZ:Biol_201:_General_Microbiology/EZnotice}}
{{Taxobox
| color = pink
| name =  Treponema Pallidium
| image =
| regnum = EUbacteria
| phylum = Spirochaetes
| classis =  Spirochaetes
| ordo =  Spirochaetales
| familia = Spirochaetacae
| genus =  Treponema
| species = T. pallidium
| binomial =
| binomial_authority = 
}}
==Description and significance==
==Genome structure==
''Treponema pallidum'' is a [[prokaryote]] with one of the smaller [[genome]]s. The organism has many processes that are similar and required for other organisms although it is dependent on the host for its survival. Like other [[eukaryotes]] it undergoes transcription, translation, replication, repair and has restriction- modification systems. Its genomic sequence is very close to that of  ''Borrelia burgdorferi'' that  causes [[Lyme Disease]] in humans. The total genome sequence of the organism has 1,138,006 base pairs. The number of base pairs of the predicted coding sequences or of the number of open reading frames is 1041.
In order to repair DNA, ''T. pallidum'' goes through methods such as uvr exision repair, mutL/mutS mismatch repair, mut Y and dat.
It lacks type 4 [[topoisomerase]] that is involved in the process of chromosome segregation. Chromosome segregation in ''T. Pallidium'' is able to occur by another mechanism that involves binding [[hemimethylated]] DNA to the cytoplasmic membrane. 
The spirochete ''T. Pallidium'' encodes for the homologs that are of the recF pathway that are involved in recombination.
==Cell structure and metabolism==
''T. pallidium'' is a microaerophile and so it needs very little oxygen for growth. It does not have genes that code for enzymes that protect against oxygen toxicity. The enzymes are present in ''B. Burgdorferi'' and include superoxide dimutase, peroxidase or catalase. It  however does have [[NADH oxidase]] which is the enzyme that utilizes oxygen in the organism.
It has an outer membrane a cytoplasmic membrane and it also consists of a thin [[peptidoglycan]] layer. Its outer membrane has relatively fewer [[integral membrane proteins]]. This permits the organism to evade the human response from the immune system.
The energy source for ''T. Pallidium'' are mainly carbohydrates like glucose, galactose and glycerol. In tissue culture system the growth and multiplication of ''T. Pallidium'' is only due to glucose, mannose and maltose. This has been an suggested due to experimental evidence.  The ''T. Pallidium'' has all the genes that code for enzymes that are required for the glycolytic pathway. ''T. Pallidium'' has homologs of the enzymes [[phosphofructokinase]] and pyruvate kinase that are there in [[eubacterial]] organisms which use [[pyrophosphate]] for energy metabolism. It does not have any of the genes that code for substances required in the [[tricarboxylic acid cycle]] or of  oxidative phosphorylation.
''T. Pallidium'' does not have a [[respiratory transport electron chain]]. ATP is therefore formed by substrate level [[phosphorylation]] and so the membrane potential is created by the reverse reaction of the enzyme ATP synthase.  The ATP synthase in the ''T.Pallidium'' is of the V1V0 type. It also has two [[operons]] of the V1V0 type and each contains seven genes.
==Pathology==
==Pathology==
''T. Pallidium'' is the causative agent of syphilis. It is transmitted through humans and cause diseases and can causes damages and previous damage done by the organism cannot be cured. It is only transmitted sexually. It can be transmitted from mother to baby. The disease it transmitted by sexual contact and it does not spread by using things that are used by others for regular purposes such as clothes, utensils, etc.  
''T. Pallidium'' is the causative agent of syphilis. It is transmitted through humans and cause diseases and can causes damages and previous damage done by the organism cannot be cured. It is only transmitted sexually. It can be transmitted from mother to baby. The disease it transmitted by sexual contact and it does not spread by using things that are used by others for regular purposes such as clothes, utensils, etc.  
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The person infected with Syphilis has a higher risk of getting HIV. The spread of the disease can be preveted by using safe sex practices.
The person infected with Syphilis has a higher risk of getting HIV. The spread of the disease can be preveted by using safe sex practices.
==Current Research==
''Treponema pallidum'' is a [[spirochete]] bacteria that has two subspecies that cause human disease. These are ''T. pallidum pallidum'', which causes [[venereal disease|venereal]] [[syphilis]]; and ''T. pallidum pertenue'', which causes [[yaws]]. Both of these subspecies are members of the family, [[Spirochaetales]], which also incudes the spirochetes ''Leptospira'', the casue of the human disease, [[leptospirosis]], and ''Borrelia'', a genus of several species of spirochetes that cause the human diseases of relapsing fever and [[Lyme disease]]. ''Treponema pallidum'' is an unusual bacterium that is particularly parasitic. It lacks the enzymes of the [[Krebs cycle]] and [[oxidative phosphorylation]], and transports many nutrients and structural substrates, such as amino acids and sugars, into its [[cytoplasm]] from its environment. This is one reason that the organism cannot live outside its host's body for any appreciable length of time and why infections must be transmitted through close contact.
Pathogenic subspecies of ''Treponema pallidum'' are very difficult to culture in the laboratory. Unlike most other bacteria that colonize and infect the human body, even special techniques for culture on artificial media are unsuccessful for the routine identification of these organisms. Instead, classically, dark field examination of a body fluid containing a large number of these spiral shaped motile bacteria was required for laboratory identification. More recently, [[PCR]] techniques are able to distinguish the organisms; this is especially helpful because both of the two subspecies of ''Treponema pallidum'', as well as other harmless species of ''Treponema'' look identical or similar under darkfield exam.
==References==
Sheila A. Lukehart. Chapter 153. "Syphilis" ''in''  Dennis L. Kasper, Eugene Braunwald, Anthony S. Fauci, Stephen L. Hauser, Dan L. Longo, J. Larry Jameson, and Kurt J. Isselbacher, Eds.Harrison's Principles of Internal Medicine, 16th Edition

Revision as of 12:41, 27 April 2009

Pathology

T. Pallidium is the causative agent of syphilis. It is transmitted through humans and cause diseases and can causes damages and previous damage done by the organism cannot be cured. It is only transmitted sexually. It can be transmitted from mother to baby. The disease it transmitted by sexual contact and it does not spread by using things that are used by others for regular purposes such as clothes, utensils, etc. The disease is spread from one person to another by contact with syphilis sores. It is spread through contact with syphilis sores that are caused by the organism. The sores can occur on the external anus, vagina, and internal anus and can also occur in the rectum. The primary stage of syphilis there is a chancre that is round and does not cause pain. It heals on its own and if the disease is not treated a person will go into the secondary and late phases of the disease. The sores can also occur in the mouth. Sometime it is not possible for a person to know whether the person has syphilis because sores occur in inside of the vagina and anus in males and females. So the person should be tested for syphilis. The secondary phase is associated with rash through out the body. If it is not treated the symptoms will go into the latent phase and it can cause damage to organs and it affect the coordination and affect the important organs and may even lead to death. Syphilis can be treated and the person at that time should avoid sexual contact. It just requires one dose of a intramuscular injection of penicillin.

The person infected with Syphilis has a higher risk of getting HIV. The spread of the disease can be preveted by using safe sex practices.