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Biochemistry
Published in Ronald Fayer, Lihua Xiao, Cryptosporidium and Cryptosporidiosis, 2007
Cryptosporidium can also make N-glycans from fructose-6P or mannose (via mannose-6P), which is required for synthesizing some glycolipids. Enzymes involved in the synthesis of amylopectin and amylose from glucose and glucose-6P, including amylopectin phosphorylase, amylopectin 1,6-glucosidase, and the branching enzyme, are all identified in the C. parvum genome. Another unique feature is the ability to synthesize trehalose via glucose-1P and UDP-glucose, which is not seen in other apicomplexans. Trehalose is commonly found in a wide range of organisms, including bacteria, fungi, plants, and some invertebrates, and may function as an antidesiccant, antioxidant, or protein-stabilizing agent (Schmatz, 1989; Michalski et al., 1992). Because the mannitol cycle found in Eimeria spp. is not present in Cryptosporidium, it is assumed that trehalose may play a role similar to mannitol in Eimeria oocysts (Schmatz, 1989; Michalski et al., 1992). Whether trehalose can serve as an energy source for Cryptosporidium is questionable, because no trehalase ortholog responsible for breaking down trehalose can be identified from the parasite genomes.
Molecular Approaches for Removal of Toxic Metal by Genetically Modified Microbes
Published in Maulin P. Shah, Wastewater Treatment, 2022
Joorie Bhattacharya, Rahul Nitnavare, Sougata Ghosh
In a study by Frederick et al. (2013), engineering of trehalose upregulation into E. coli led to an increase in tolerance toward chromate and a reduction in cumulative concentration of Cr(VI). Several organic molecules present within the biological system possess the capacity of the protective effect without hindering essential pathways and functions. One such compound, trehalose, is capable of providing protection against osmotic shock; preservation of physical composition of cell under stress; preventing DNA and protein denaturation, dehydration, and extreme temperatures. E. coli was engineered to overproduce trehalose by expression of the OtsA/OtsB protein. The MC4100 strain of the bacteria is well known to produce trehalose governed by the otsA and otsB genes. Strains with mutations in the otsA gene produced reduced concentrations of trehalose. Overexpression of trehalose was achieved by introducing an operon encoding otsA and otsB with an arabinose-inducible promoter. The trehalose production in bacteria overexpressing trehalose, wild type, and otsA mutant bacteria was found to be 262 ± 74 mM, 15 ± 12 mM, and 2 ± 3 mM, respectively. The ability of the bacteria to convert Cr(III) to Cr(VI) was also accessed and it was found that while the wild type was able to reduce half of the chromate, the trehalose overproducer was able to convert almost all of the chromate into its less toxic trivalent form. This trend was observed for up to 1 mM of Cr(VI). Use of trehalose as a chemical protectant against chromate thus can prove to be a promising approach for chromium bioremediation.
Excipients for Parenteral Use
Published in Sandeep Nema, John D. Ludwig, Parenteral Medications, 2019
Sandeep Nema, Ronald J. Brendel
Trehalose is a non-reducing disaccharide composed of two D-glucose monomers. It is found in some plants and animals which can withstand dehydration (anhydrobiosis) and therefore had been suggested to stabilize drugs which undergo denaturation during spray or freeze-drying.69 Herceptin® (Trastuzumab) is a recombinant DNA-derived monoclonal antibody (MAb) used for treating metastatic breast cancer. The MAb is stabilized in the lyophilized formulation using α,α-trehalose dihydrate. Trehalose is also used as a cryoprotectant to prevent liposomal aggregation and leakage. In the dried state, carbohydrates like trehalose and inositol exert their protective effect by acting as a water substitute.70
Molecular movements of trehalose inside a single network enabling a rapidly-recoverable tough hydrogel
Published in International Journal of Smart and Nano Materials, 2022
Xiaowen Huang, Jimin Fu, Huiyan Tan, Yan Miu, Mengda Xu, Qiuhua Zhao, Yujie Xie, Shengtong Sun, Haimin Yao, Lidong Zhang
Above analysis indicates that introducing movable components into PAM network might be a feasible strategy for developing highly recoverable hydrogels. In this work, we demonstrated this conception by applying trehalose (Tre) as a movable physical cross-linker to improve the reversible kinetics of hydrogen-bonding interaction inside a single network. Trehalose is a type of non-reducing disaccharide, composed of two glucose molecules. One trehalose molecule contains eight hydroxyl groups, offering many functional sites for non-covalent bonding interaction (e.g. hydrogen bond). In the meantime, it is a low-molecular-weight molecule with the size <1 nm[19], which, when hybridized into PAM network, is expected to move inside the PAM network and facilitates the reconstruction of the broken hydrogen bonds (Figure 1d).
Comprehensive optimization of composite cryoprotectant for Saccharomyces boulardii during freeze-drying and evaluation of its storage stability
Published in Preparative Biochemistry & Biotechnology, 2019
Shu Guowei, Xin Yang, Chen Li, Dan Huang, Zhangteng Lei, Chen He
Sugars such as trehalose and sucrose are commonly used as cryoprotectants or lyoprotectants. Trehalose, as a disaccharide, is a natural cryoprotectant and has been successfully utilized to preserve different cell types during freeze-drying including bacterial and yeast cells.[36,37] Adding a certain amount of trehalose may either form a thicker glass layer surrounding the dehydrated spores, or enhance the amount of hydrogen bonding in phospholipid head groups.[38,39] More important, it has been proved that the trehalose would protect proteins against denaturation.[40] Choi et al.[41] observed that the highest survival rate of Saccharomyces cerevisiae was occurred by using the saccharose and trehalose as protective agents.
The role of disaccharides for protein–protein interactions – a SANS study
Published in Molecular Physics, 2019
Christoffer Olsson, Jan Swenson
In this study, we investigated whether or not the extraordinary protein-stabilisation effect of trehalose was specifically related to its ability to prevent protein–protein interactions. This effect was studied by the use of small-angle neutron scattering in combination with isotopic substitution, and the superior stabilising effect of trehalose was checked with the use of determining the denaturation temperature in either trehalose or sucrose solutions. According to the analysis of the SANS data, both sucrose and trehalose separate the protein molecules to approximately the same distances of 40.5 Å, which corresponds to about 8–10 Å of solvent separating proteins from each other. This was interestingly found to be in quite stark contrast to the investigated two-component system containing water and myoglobin, which exhibited a protein–protein distance only permitting about a single water layer. This indicates that both sugar molecules act by separating the protein molecules, which thereby is not an effect specific to trehalose. Furthermore, we found no other significant large-scale structures in either sugar solution, which has otherwise been reported at lower water contents [33,34]. Instead, we propose that the origin of the superior anti-aggregation and protein stabilisation effects provided by trehalose can be found in their solvent structure and dynamics, which has previously been suggested by others in the literature [50]. An analysis of such structures in both trehalose and sucrose systems is currently being conducted by us with the use of neutron diffraction and EPSR modelling. Further understanding of how trehalose act as an anti-aggregation agent can be useful for the study of such molecules for the treatment against protein aggregation related diseases, such as Alzheimer’s and Huntington’s disease.