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The Leu99-->Ala mutant of T4 lysozyme contains a large internal cavity in the core of its C-terminal domain that is capable of reversibly binding small hydrophobic compounds. Although the cavity is completely buried, molecules such as benzene or xenon can exchange rapidly in and out. The dynamics of
Ligand binding sites in proteins are often localized to deeply buried cavities, inaccessible to bulk solvent. Yet, in many cases binding of cognate ligands occurs rapidly. An intriguing system is presented by the L99A cavity mutant of T4 Lysozyme (T4L L99A) that rapidly binds benzene (~106 M-1s-1).
OBJECTIVE
The present study is conducted to compare the anti-microbial efficacy of tooth paste containing lactoferrin, lysozyme, lactoperoxidase (BioXtra ®), a 500ppm fluoride tooth paste, and a non fluoridated tooth paste in children with Severe Early Childhood Caries (S-ECC).
METHODS
Study group
Although the structure, function, conformational dynamics, and controlled thermodynamics of proteins are manifested by their corresponding amino acid sequences, the natural rules for molecular design and their corresponding interplay remain obscure. In this study, we focused on the role of internal
It is well known that high hydrostatic pressures can induce the unfolding of proteins. The physical underpinnings of this phenomenon have been investigated extensively but remain controversial. Changes in solvation energetics have been commonly proposed as a driving force for pressure-induced
OBJECTIVE
To explore the relationship between the concentrations of lactoferrin and lysozyme in saliva and dental caries in primary dentition among Chinese children.
METHODS
Forty children with high dmft score (dmft > or = 5) and 40 caries-free children (dmft = 0) were sampled and assigned into two
Abstract Wild waterfowl species often nest in conditions where high humidity and microbial contamination may influence egg survival and quality. Albumen is traditionally regarded as the major impediment to microbial contamination of eggs, and its composition and activity may be selected by
We have used low temperatures (down to -20°C) and high pressures (up to 2000 bar) to populate low-lying excited state conformers of hen lysozyme, and have analyzed their structures site-specifically using (15)N/(1)H two-dimensional HSQC NMR spectroscopy. The resonances of a number of residues were
To probe the nature of the hydrophobic cores of proteins and to test potential ways of increasing protein thermostability, an attempt was made to improve the packing within T4 bacteriophage lysozyme by engineered amino acid replacements. Two mutations, Leu-133----Phe and Ala-129----Val, which were
Stabilization of a protein using cavity-filling strategy has hardly been successful because of unfavorable van der Waals contacts. We succeeded in stabilizing lysozymes by cavity-filling mutations. The mutations were checked by a simple energy minimization in advance. It was shown clearly that the
Wild-type bacteriophage T4 lysozyme contains a hydrophobic cavity with binding properties that have been extensively studied by X-ray crystallography and NMR. In the present study, the monitoring of 1H chemical shift variations under xenon pressure enables the determination of the noble gas binding
Amino acid substitutions were examined to increase the stability of the mutant human lysozyme C77/95A by filling the cavity created by this mutation. To modulate the cavity with hydrophobic amino acids or by the formation of a hydrogen bond, five amino acid-substituted mutants, C77AC95L, C77AC95I,
To investigate the relative importance of size and polarizability in ligand binding within proteins, we have determined the crystal structures of pseudo wild-type and cavity-containing mutant phage T4 lysozymes in the presence of argon, krypton, and xenon. These proteins provide a representative
Both large-to-small and nonpolar-to-polar mutations in the hydrophobic core of T4 lysozyme cause significant loss in stability. By including supplementary stabilizing mutations we constructed a variant that combines the cavity-creating substitution Leu99 --> Ala with the buried charge mutant Met102
OBJECTIVE
The objective of this study was to analyze salivary lysozyme levels and activities in Thai preschoolers with different dental caries status.
METHODS
Unstimulated saliva samples were collected from 64 preschoolers, divided into a caries free group (n = 32) and a severe early childhood