The Trigger Factor

The trigger factor was discovered by Crooke and Wickner in 1987 when they searched for cytosolic components involved in the export of secretory proteins from E. coli (Crooke and Wickner, 1987 Lill et al., 1988). They found that trigger factor binds to and thus stabilizes the export-competent form of a precursor protein, proOmpA. The trigger factor is an abundant soluble protein, which associates with the large subunit 

In 1995, Fischer and co-workers (Stoller et al., 1995) discovered that trigger factor is a ribosome-associated prolyl isomerase. The enzymatic activity originates from a central FKBP domain, which encompasses residues 142—251 (Callebaut and Momon, 1995 Hesterkamp and Bukau, 1996 Stoller et al., 1996). When protein translation is arrested, nascent protein chains can be crosslinked to the trigger factor at the ribosome (Valent etal., 1995 Hesterkamp et al., 1996). The N-terminal domain of the trigger factor (residues 1—118) mediates the interaction with the ribosome (Hesterkamp et al., 1997) the function of the C-terminal domain is unknown. 

Catalysis of Proline-Limited Folding by the Trigger Factor 

Permanently unfolded proteins are strong, competitive inhibitors of trigger-factor-catalyzed folding. One of those, reduced and 

Bacillus subtilis contains only two prolyl isomerases—PPIB, which is a cytosolic cyclophilin, and trigger factor. Disruption of the corresponding genes individually or in combination had no effect on viability of 

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Entry into and the course of mitosis are primarily determined by the activity of the CDC2 kinase. The CDC2 kinase in the active form exists as a complex with cychn B and, together with the cyclin, forms the mitosis promoting factor, MPF. The activity of MPF oscillates in the cell cycle and is the triggering factor for entry of the cell into M phase. 

The acute or acute recurrent form can be equated with the manifestation of portosystemic encephalopathy in chronic liver disease. It is also known as acute episodic form . Discrete psychometric disorders usually precede the manifest picture as a latent stage. Manifestation includes stages I-IV and hence covers a wide spectrum of clinical, neurological and psychopathological symptoms. Once the liver function is stabilized and the trigger factors are eliminated, all the symptoms of this form are as a rule reversible. 

The prognosis also depends on the trigger factors of HE being eliminated as rapidly and as completely as possible. This is particularly true of the swiftest possible elimination of blood from the intestinal tract. 

Aldesleukin was thought to be the triggering factor in the occurrence of sarcoidosis in a 36-year-old patient with AIDS stabilized for a long time by highly active antiretroviral therapy (111). 

These cases usually occur in relatively young people, often smokers, and the prognosis after the acute phase is usually good if the triggering factors that produced the hypercoagulation state are suppressed. We have followed a smoker for more than 40 years who presented a large anterior Q-wave infarction at the age of 39. 

There is evidence that the trigger factor and the hsp70 chaperone DnaK, a PPIase and a secondary amide peptide bond cis-trans isomerase (APIase) respectively, contribute to the formation of native proteins by apparently overlapping functions with the trigger factor as the primary interaction partner of the emerging polypeptide chain [122-124]. Consequently, synthetic lethality was observed... 

Among the plethora of NMR and crystallographic structures available in the Broo-khaven Protein Data Bank, most concern either cyclophilin alone or assodated with various substrates and effectors (81 structures). FKBP structures have essentially been resolved alone or bound to their effectors, including inhibitors (45 structures including MIP). Pinl, Par 14, and ESS1 (respectively 8, 4, and 1 structures) and the trigger factor (7 structures) are also represented [12]. 

A. Catalysis of Proline-Limited Folding by the Trigger Factor. 265... 

The trigger factor of E. coli also contains a FKBP domain. This prolyl isomerase locates to the ribosome of bacteria and is an excellent catalyst of protein folding. It is described in Section IX. Additional proteins with cyclophilin- or FKBP-related domains have been described (Anderson etal., 1993 Fischer, 1994 Galatand Metcalfe, 1995 Heitman, 1997 Galat and Riviere, 1998). 

Looking at the historical development of the emulsion pol)nnerization, it is seen that the trigger factor in this development was the necessity for synthetic rubber in the wartime. The production of styrene/butadiene rubber (SBR) satisfied this requirement. Today, millions of tons of S)mthetic latexes are produced by the emulsion pol3merization process for use in wide variety of applications. In the S)mthetic latexes, the most important groups are styrene/butadiene copolymers, vinyl acetate homopol)rmers and copol)nners, and polyacrylates. Other synthetic latexes contain copolymers of ethylene, styrene, vinyl esters, vinyl chloride, vinylidene chloride, acrylonitrile, cloroprene and polyurethane. 

The dynamics of the development of occupational hand eczema are not fully understood, but irritation and contact sensitivity, together with individual constitutional factors, influence its development. Theoretically, at least one of the triggering factors could be eliminated if the workers used individual preventive measures. Use of gloves, protective hand creams and hand washing were not found to influence the propensity for developing irritant cement eczema (Avnstorp 1991). Furthermore, no additional effect was found from individual preventive measures. The absence of influence from individual preventive measures could be explained by the possibility that the work processes are so hazardous that they overwhelm the protective effect. It could also be that the preventive initiatives were not conducted systematically or carefully enough. 

Zhiyang valley has sufficient amount of loose solid material as material source and a site condition of large gradient. Heavy rainfall is the triggering factor. The debris flow in Zhiyang valley is the rainfall valley debris flow. 

The authors reviewed 29 other cases of (3-blocker-associated LDE, where atenolol was the most frequently responsible drug. They concluded that LDE is a relatively rare complication and it may present as classic lichenoid papules that are indistinguishable from lichen planus. The triggering factors of p-blocker-associated LDE may be due to drug cross-reactivity or a result of a suppressed skin adrenergic system. 

The description of present or past processes for the commercial production of PHAs have been the subject of recent reviews [75, 135, 227, 228]. Current industrial PHBV production utilizes a glucose-assimilating strain of R. eutropha in fed-batch regime with phosphate limitation as the triggering factor for biopolymer accumulation and propionic acid as 3HV precursor [227]. For convenience, this R. eutropha cdihohydsdiid propionate combination in fed-batch mode will be referred to here as a conventional strategy for production of PHBVs. 

If the patient has symptoms, treatment may focus on eliminating or controlling the trigger factor, such as caffeine or alcohol consumption. 

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