Difference between revisions of "Part:BBa K541025"
 
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On the other hand, Lipopolysaccharide (LPS), or endotoxin, is the major mediator of septic shock, a serious complication of Gram-negative bacterial infections in humans. Molecules that bind LPS and neutralize its biological effects or enhance its clearance could have important clinical applications. Limulus anti-LPS factor (LALF) binds LPS tightly, and, in animal models, reduces mortality when administered before or after LPS challenge or bacterial infection. The wedge- shaped molecule has a striking charge distribution and amphipathicity that suggest how it can insert into membranes. The binding site for LPS probably involves an extended amphipathic loop, and it has been proposed that two mammalian LPS-binding proteins will have a similar loop. The amphipathic loop structure may be used in the design of molecules with therapeutic properties against septic shock.  
 
On the other hand, Lipopolysaccharide (LPS), or endotoxin, is the major mediator of septic shock, a serious complication of Gram-negative bacterial infections in humans. Molecules that bind LPS and neutralize its biological effects or enhance its clearance could have important clinical applications. Limulus anti-LPS factor (LALF) binds LPS tightly, and, in animal models, reduces mortality when administered before or after LPS challenge or bacterial infection. The wedge- shaped molecule has a striking charge distribution and amphipathicity that suggest how it can insert into membranes. The binding site for LPS probably involves an extended amphipathic loop, and it has been proposed that two mammalian LPS-binding proteins will have a similar loop. The amphipathic loop structure may be used in the design of molecules with therapeutic properties against septic shock.  
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Reflectin Proteins
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Many cephalopods (octopuses, squids, cuttlefish, etc.) demonstrate camouflage capabilities by adaptive transparency. Some chalepods can even vanish from the environment by performing these capabilities. These animals can change the optical properties of their skin, how their skin transmits, absorbs, and reflects light [3]. Reflectivity in these animal tissues is achieved by stacking flat, insoluble, structural platelets by alternating layers of high and low refractive index in iridocytes [4]. This alternate arrangement, called a Bragg reflector, creates a thin-film interference pattern which is the reason for reflection of incident light from the tissue [3]. In aquatic animals, reflector platelets generally consist of purine crystals, particularly guanine and hypoxanthine. However, cephalopod reflector platelets contain reflectin proteins instead of these purine crystals. Reflectin proteins found in cephalopods are responsible for transparency abilities by employing structural coloration and iridescence [1, 2].
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Optical characterization of these proteins is an important work for studies using reflectin proteins. However, it is hard to characterize the refractive index of these proteins since there are multiple Bragg stacks with unknown variation in spacings, refractive indices and orientations in a typical tissue of a chalepod. Ghoshal et al (2014) employed a microspectroscopy procedure to investigate these properties. They found a progressively higher refractive index from 1.33 to 1.43 from the same Bragg stack as they immersed these Bragg stacks in solutions of different reflectivities.
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[1] Junko Ogawa et al. (2020) Genetic manipulation of the optical refractive index in living cells https://doi.org/10.1101/2020.07.09.196436
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[2] Atrouli Chatterjee et al. (2020) Cephalopod-inspired optical engineering of human cells https://doi.org/10.1038/s41467-020-16151-6
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[3] Wendy J. Crookes et al. (2004) Reflectins: The Unusual Proteins of Squid Reflective Tissues https://doi.org/10.1126/science.1091288
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[4] Amitabh Ghoshal et al. (2014) Experimental determination of refractive index of condensed reflectin in squid iridocytes http://dx.doi.org/10.1098/rsif.2014.0106 Sequence and Features
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===Usage and Biology===
 
===Usage and Biology===
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Latest revision as of 12:22, 28 September 2020

Reflectin 1A (LipA) and LALF (SacB) protein for B.subtilis

Reflectin is a self-assembling protein that has the ability to reflect the sun light which depends on the thickness of the protein layer. Therefore, we thought that this ability could be used as a novel reporter for B.subtilis and E.coli.

On the other hand, Lipopolysaccharide (LPS), or endotoxin, is the major mediator of septic shock, a serious complication of Gram-negative bacterial infections in humans. Molecules that bind LPS and neutralize its biological effects or enhance its clearance could have important clinical applications. Limulus anti-LPS factor (LALF) binds LPS tightly, and, in animal models, reduces mortality when administered before or after LPS challenge or bacterial infection. The wedge- shaped molecule has a striking charge distribution and amphipathicity that suggest how it can insert into membranes. The binding site for LPS probably involves an extended amphipathic loop, and it has been proposed that two mammalian LPS-binding proteins will have a similar loop. The amphipathic loop structure may be used in the design of molecules with therapeutic properties against septic shock.

Reflectin Proteins

Many cephalopods (octopuses, squids, cuttlefish, etc.) demonstrate camouflage capabilities by adaptive transparency. Some chalepods can even vanish from the environment by performing these capabilities. These animals can change the optical properties of their skin, how their skin transmits, absorbs, and reflects light [3]. Reflectivity in these animal tissues is achieved by stacking flat, insoluble, structural platelets by alternating layers of high and low refractive index in iridocytes [4]. This alternate arrangement, called a Bragg reflector, creates a thin-film interference pattern which is the reason for reflection of incident light from the tissue [3]. In aquatic animals, reflector platelets generally consist of purine crystals, particularly guanine and hypoxanthine. However, cephalopod reflector platelets contain reflectin proteins instead of these purine crystals. Reflectin proteins found in cephalopods are responsible for transparency abilities by employing structural coloration and iridescence [1, 2].

Optical characterization of these proteins is an important work for studies using reflectin proteins. However, it is hard to characterize the refractive index of these proteins since there are multiple Bragg stacks with unknown variation in spacings, refractive indices and orientations in a typical tissue of a chalepod. Ghoshal et al (2014) employed a microspectroscopy procedure to investigate these properties. They found a progressively higher refractive index from 1.33 to 1.43 from the same Bragg stack as they immersed these Bragg stacks in solutions of different reflectivities.


[1] Junko Ogawa et al. (2020) Genetic manipulation of the optical refractive index in living cells https://doi.org/10.1101/2020.07.09.196436

[2] Atrouli Chatterjee et al. (2020) Cephalopod-inspired optical engineering of human cells https://doi.org/10.1038/s41467-020-16151-6

[3] Wendy J. Crookes et al. (2004) Reflectins: The Unusual Proteins of Squid Reflective Tissues https://doi.org/10.1126/science.1091288

[4] Amitabh Ghoshal et al. (2014) Experimental determination of refractive index of condensed reflectin in squid iridocytes http://dx.doi.org/10.1098/rsif.2014.0106 Sequence and Features



Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    COMPATIBLE WITH RFC[1000]