Biology subjects

Fetrow, B.

Publications and source records attributed to Fetrow, B..

3 recordsLinked to original sources

bioRxiv2021

Rapid and Effective Inactivation of SARS-CoV-2 by a Cationic Conjugated Oligomer with Visible Light: Studies of Antiviral Activity in Solutions and on Supports

This paper presents results of a study of a new cationic oligomer that contains end groups and a chromophore affording inactivation of SARS-Cov-2 by visible light irradiation in solution or as a solid coating on wipes paper and glass fiber filtration substrates. A key finding of this study is that the cationic oligomer with a central thiophene ring and imidazolium charged groups give outstanding performance in both killing of E. coli bacterial cells and inactivation of the virus at very short times. Our introduction of cationic N-Methyl Imidazolium groups enhances the light-activation process for both E. coli and SARS-Cov-2 but dampens the dark killing of the bacteria and eliminates the dark inactivation of the virus. For the studies with this oligomer in solution at concentration of 1 g/mL and E. coli we obtain 3 log killing of the bacteria with 10 min irradiation with LuzChem cool white lights (mimicking indoor illumination). With the oligomer in solution at a concentration of 10 g/mL, we observe 4 logs inactivation (99.99 %) in 5 minutes of irradiation and total inactivation after 10 min. The oligomer is quite active against E. coli on oligomer-coated wipes papers and glass fiber filter supports. The SARS-Cov-2 is also inactivated by the oligomer coated glass fiber filter papers. This study indicates that these oligomer-coated materials may be very useful as wipes and filtration materials.

biochemistry↗

bioRxiv2020

Ultrasensitive small molecule fluorogenic probe for human heparanase

Heparanase is a critical enzyme involved in the remodeling of the extracellular matrix (ECM), and its elevated expression has been linked with diseases such as cancer and inflammation. The detection of heparanase enzymatic activity holds tremendous value in the study of the cellular microenvironment, and search of molecular therapeutics targeting heparanase, however, assays developed for this enzyme so far have suffered prohibitive drawbacks. Here we present an ultrasensitive fluorogenic small-molecule probe for heparanase enzymatic activity. The probe exhibits a 756-fold fluorescence turn-on response in the presence of human heparanase, allowing one-step detection of heparanase activity in real-time with a picomolar detection limit. The high sensitivity and robustness of the probe are exemplified in a high-throughput screening assay for heparanase inhibitors.

biochemistry↗

bioRxiv2020

Internally quenched fluorogenic probe provides selective and rapid detection of cathepsin L activity

Cathepsin L (CTL) is a cysteine protease that demonstrates upregulated activity and/or altered trafficking during disease states such as cancer. The overlapping substrate specificity of cathepsin family members makes selective detection of activity from a single cathepsin difficult, and CTL activity is particularly difficult to parse from its close homologue CTV and the ubiquitous CTB. Despite this, screening campaigns have explored the extended chemical space in the cathepsin binding sites and identified unique substrate structures that offer selectivity for one enzyme over others. In this vein, we present CTLAP, a fluorogenic probe that is rapidly activated by CTL and displays good selectivity over CTB and CTV, the closest competing analytes for CTL activity probes. CTLAP exhibits intrinsically low background fluorescence, which we attribute to possible self-quenching mechanisms. CTLAP demonstrates markedly higher turn-on ratios (24-fold) and moderately improved enzyme selectivity compared to Z-FR-AMC (10-fold turn-on ratio), a commercially available CTL-selective probe commonly used to detect CTL activity in mixed samples. Optimum selectivity for CTL is achieved within 10 min of incubation with the enzyme, suggesting that CTLAP is amenable for rapid detection of CTL, even in the presence of competing cathepsins.

biochemistry↗