4 research outputs found
Influence of Fluorination on Protein-Engineered Coiled-Coil Fibers
We
describe the design and characterization of fluorinated coiled-coil
proteins able to assemble into robust nano- and microfibers. Fluorination
is achieved biosynthetically by residue-specific incorporation of
5,5,5-trifluoroleucine (TFL). The fluorinated proteins C+TFL and Q+TFL
are highly α-helical as confirmed via circular dichroism (CD)
and more resistant to thermal denaturation compared to their nonfluorinated
counterparts, C and Q. The fluorinated proteins demonstrate enhanced
fiber assembly at pH 8.0 with higher order structure in contrast to
nonfluorinated proteins, which are unable to form fibers under the
same conditions. Ionic strength dependent fiber assembly is observed
for fluorinated as well as wild-type proteins in which the fluorinated
proteins exhibited more stable, thicker fibers. The fluorinated and
nonfluorinated proteins reveal metal ion-dependent small molecule
recognition and supramolecular assemblies. In the presence of Zn (II),
enhanced thermal stability and fiber assembly is observed for the
fluorinated proteins and their nonfluorinated counterparts. Whereas
Ni (II) promotes aggregation with no fiber assembly, the stabilization
of α-helix by Zn (II) results in enhanced binding to curcumin
by the fluorinated proteins. Surprisingly, the nonfluorinated proteins
exhibit multiple-fold increase in curcumin binding in the presence
of Zn (II). In the context of the growing number of protein-based
fiber assemblies, these fluorinated coiled-coil proteins introduce
a new paradigm in the development of highly stable, robust self-assembling
fibers under more physiologically relevant pH conditions that promotes
the binding and release of small molecules in response to external
cues
Efficient Dual siRNA and Drug Delivery Using Engineered Lipoproteoplexes
An
engineered supercharged coiled-coil protein (CSP) and the cationic
transfection reagent Lipofectamine 2000 are combined to form a lipoproteoplex
for the purpose of dual delivery of siRNA and doxorubicin. CSP, bearing
an external positive charge and axial hydrophobic pore, demonstrates
the ability to condense siRNA and encapsulate the small-molecule chemotherapeutic,
doxorubicin. The lipoproteoplex demonstrates improved doxorubicin
loading relative to Lipofectamine 2000. Furthermore, it induces effective
transfection of GAPDH (60% knockdown) in MCF-7 breast cancer cells
with efficiencies comparing favorably to Lipofectamine 2000. When
the lipoproteoplex is loaded with doxorubicin, the improved doxorubicin
loading (∼40 μg Dox/mg CSP) results in a substantial
decrease in MCF-7 cell viability
Findings from a community education needs assessment to facilitate the integration of genomic medicine into primary care
To assess the lay public's knowledge of, and beliefs about, genetics and genetic testing to create an educational initiative that promotes acceptance and utilization of genomic medicine in primary health care.
A telephone survey of English-speaking adults in Guilford County, North Carolina was conducted in 2006 to identify community members' educational needs regarding genetics and genetic testing.
Most respondents recognized the connection between family history and disease risk. A majority did not appear to know about: (1) basic principles of inheritance, (2) laws prohibiting genetic discrimination, and (3) the availability and limitations of genetic tests. About 25% thought that they could not reduce their risk if they have a genetic predisposition for disease. Knowledge level was affected by education, experience, age, and race.
If primary care providers use family history as a risk assessment tool, community education programs must address (1) the collection of family health history, (2) legislation regarding genetic nondiscrimination, (3) benefits and limitations of existing genetic tests, and (4) genetic determinism. Programs emphasizing practical, "how to" information can be targeted to individuals likely to collect family history information and address misperceptions about discrimination, testing, and determinism