Effects of large anphiphilic ligands upon the spectra and kinetics of cytochrome C oxidase

Cytoch ro me c oxidase (ferrocytochrome c : 02 oxidoreductase ; EC 1.9. 3.1) is the terminal enzyme in the mitochondrial electron transport chain, catalyzing the transfer of electrons from ferrocytochrome c to molecular oxygen. The effects of two large amphiphilic molecules .. valinomycin and dibucaine upon the spectra of the isolated enzyme and upon the activity of both isolated enzyme and enzyme in membrane systems are investigated by using spectrophotometric and oxygen electrode techniques. The results show that both valinomycin and dibucaine change the Soret region of the spectrum and cause a partial inhibition in a concentration range higher than that in which they act as ionophores. It is concluded that both valinomycin and dibucain~ binding induce a conformational change of the protein structure which modifies the spectrum of the a3 CUB centre and diminishes the rate of electron transfer between cytochrome a and the binuclear centre.

Perceptions of leadership in adolescent girls, members of the Girl Guides of Canada

Twenty-eight young women who were members of the Girl Guides of Canada as Rangers and Cadets from a convenience sample chose to participate in this case study. They were from four separate locations in Southern Ontario. The interviews and observations at unit meetings allowed an indepth look into the perceptions of leadership of these young women. The amount of time observing and interacting with each participant provided a snapshot of what they thought and how they responded to the questions asked at that particular time. Each girl responded to the question, "Are you a leader?" They then gave examples of their own leadership and described leaders they knew. Their responses are reported in relation to their definitions. Their identifications of effective and ineffective leaders were examined, as well as their views of the best and worst things a leader can do. This information is reported by unit, as some patterns in their responses emerged which were unique to each group. The responses of all of the girls to the leadership of Guiders, Rangers and Cadets and the hypothetical effect of male leaders and male Rangers in Guiding are reported. For these, the participants' views were sorted based on the common themes/ and regardless of their group affiliation, since many of the same themes emerged when examining these questions. The information collected was extensive and allowed for trends and parallels to become evident 0 All of the participants identified themselves as leaders. A diversity of views exists in their perceptions of leadership. For many, age makes a difference in leadership. The majority identified the single-sex aspect of the organization as comfortable and stated that it should remain so. Gender profoundly affects who is listened to and what opportunities are available.

Effects of large anphiphilic ligands upon the spectra and kinetics of cytochrome C oxidase

Cytoch ro me c oxidase (ferrocytochrome c : 02 oxidoreductase ; EC 1.9. 3.1) is the terminal enzyme in the mitochondrial electron transport chain, catalyzing the transfer of electrons from ferrocytochrome c to molecular oxygen. The effects of two large amphiphilic molecules - valinomycin and dibucaine upon the spectra of the isolated enzyme and upon the activity of both isolated enzyme and enzyme in membrane systems are investigated by using spectrophotometric and oxygen electrode techniques. The results show that both valinomycin and dibucaine change the Soret region of the speetrum and cause a partial inhibition in a concentration range higher than that in which they act as ionophores. It is concluded that both valinomycin and dibucaine binding induce a conformational change of the protein structure which modifies the spectrum of the a3 CUB centre and diminishes the rate of electron transfer between cytochrome a and the binuclear centre.