Paper-based DNA biosensors are powerful tools in point-of-care diagnostics since they affordable, portable, user-friendly, rapid and robust. However, their sensitivity is not always as high required to enable quantification. To improve the response of standard dot blots, we have applied a new enhancement strategy that increases assays based on use biotinylated silica-nanoparticles (biotin-Si-NP...

Osteoclasts are induced by macrophage colony-stimulating factor-1 (CSF-1) and receptor activator of nuclear factor-?B (RANK) ligand (RANKL). Monocyte/macrophage lineages thought to be osteoclast precursors; however, such cells have not been fully characterized owing a lack tools for their identification. Osteoclast precursors express (CSF-1R) RANK. However, the capacity conventional methods usi...

Several lines of evidence indicate that biotin is involved in the biological fixation of carbon dioxide. Lardy, Potter, and Elvehjem (1) have demonstrated that the biotin requirement of Lactobacillus arabinosus is partially replaceable by oxalacetate and that the growth stimulation of this organism by carbon dioxide is evident only when biotin is present. From microbiological studies with antim...

We have developed a simple, fast, accurate, and reproducible method--an Enzyme-Linked Ligand Sorbent Assay (ELLSA)--for quantifying biotin without the use of isotopes and immunological reagents. The analytical principle is based on the competition between biotin of the sample and immobilized biotin, i.e., biotinylated bovine serum albumin coated onto immunoplates, for binding to horseradish per...

The effect of biotin on the induction (and possible requirement for uptake into mitochondria) of apopyruvate carboxylase has been examined in 3T3-L adipocytes. Cells fed biotin-sufficient medium contained only holoenzyme in mitochondria and no apoenzyme was detected. The amount of apoenzyme elaborated in biotin-deficient 3T3-L adipocytes was comparable to the holopyruvate carboxylase protein fo...

Liver acetyl-CoA carboxylase, a biotin-enzyme which catalyzes the ATP-dependent carboxylation of acetyl-CoA (acceptor) to form malonyl-CoA (carboxylated acceptor), decarboxylates malonyl-CoA by a biotin-dependent, as well as a biotin-independent mechanism. Neither ADP, Pi, nor divalent metal ion are required for either of these abortive decarboxylations. The biotin-dependent reaction is blocked...

The contribution of cysteine desulfurase, the NifS protein of Klebsiella pneumoniae and the IscS protein of Escherichia coli, to the biotin synthase reaction was investigated in in vitro and in vivo reaction systems with E. coli. When the nifS and nifU genes of K. pneumoniae were coexpressed in E. coli, NifS and NifU proteins in complex (NifU/S complex) and NifU monomer forms were observed. Bot...

Previous investigations have shown that biotin deficiency in Streptococcus lactis 8039 is associated with the loss in ability to convert ornithine and carbamyl phosphate to citrulline (1). Although protein synthesis in the presence of biotin was found to be necessary to restore completely the ornithine-citrulline enzyme activity of the biotin-deficient cells (2), a preliminary report on the bio...

Avidin, which is one type of glycoprotein, has a strong affinity with biotin (Ka = 10(15) M(-1)). Iminobiotin also forms a complex with avidin (Ka = 10(8) M(-1) at pH 9.5). The avidin-iminobiotin complex changes to the avidin-biotin complex in the presence of biotin because of the difference of the binding constant to avidin. In this study, the interaction between avidin and iminobiotin labeled...