Cytochrome b6f complex Essay Example | Topics and Well Written Essays - 2500 words

Cytochrome b6f complex - Essay Example As one of the major photosynthetic protein that is widely been explored in the study of biochemistry, the cytochrome b6f complex is commonly found not only in green algae but also in cyanobacteria (Baniulis et al., 2009; Whitelegge et al., 2002). Each time the plants undergo photosynthesis, the cytochrome b6f complex plays a significant role in the process of transferring the electro-chemical proton 11 across the thylakoid membrane (Laisk, Nedbal and Govindjee, 2009, p. 159). In other words, the thylakoid membrane in plants is responsible in introducing some protons within the close surroundings of the thylakoid. As part of analyzing the biochemistry and role of cytochrome b6f complex in the photosynthesis of plants, this study will purposely gather and make use of several scientific-based literature in discussing not only the relationship between the Cytochrome b6f complex and its biochemical structure but also the basic modes of enzyme catalysis in relation to some specific example s. Relationship between Functions of Cytochrome b6f Complex to their Structures To be able to clearly explain the relationship betwen the functions of cytochrome b6f complex and its biochemical structure, it is necessary to first explore the biochemical structure of cytochrome b6f complex followed by discussing the main function of cytochrome b6f complex. ... According to Whitelegge et al. (2002), the structure of cytochrome b6f complex is complex due to the fact that cytochrome b6f complex is composed of as much as eight (8) different polypeptide subunits (Baniulis et al., 2009; Dashdorj et al., 2005; Genji et al., 2004). In line with this, several studies strongly suggest that cytochrome b6f complex is complex since it is composed of a total of seven (7) prosthetic groups (Baniulis et al., 2008; Cramer et al., 2004). Several studies explained that the structure of cytochrome b6f complex is composed of four large subunits between 17 to 32 kDa such as the membrane bound c-type cytochrome f (PetA), cytochrome b6 (PetB), the Rieske iron-sulfur protein which is also known as the Rieske ISP (PetC), and the subunit IV (PetD) (Baniulus et al., 2011; Cramer, Hasan and Yamashita, 2011; Yan and Cramer, 2003; Schneider et al., 2002; Whitelegge et al., 2002). According to Baniulus et al. (2011), petA, petB, petC, and petD are classified as large sub units that can interact well with the redox-active prosthetic groups. Serving as the â€Å"picket fence† type of structure that surrounds the core of cytochrome b6f complex’s four (4) larger subunits, the structure of cytochrome b6f complex is also composed of four (4) other hydrophobic subunits (3.2 to 4.2 kDa) which include the PetG, PetL, PetM, and PetN (Baniulus et al., 2011; Whitelegge et al., 2002). For example, Kugler et al. (1998) mentioned that the chloroplast cytochrome b6f complex is composed of seven (7) different subunits including very small proteins such as PetG, PetL, and PetM proteins. After conducting an ex-ray structure analysis, Genji et al. (2004) found out that the biochemical structure of cytochrome b6f complex in blue-green algae is crystal in form. Because of

Sustainable Land Management in Latin America Essay -- Environment Envi

Sustainable Land Management in Latin America â€Å"The enthusiastic celebration of indigenous skills can be the basis of alternative strategies of development.† – W.M. Adams Introduction The sustainability of land management practices in developing countries is in question currently as a way to address poverty. Yet, this investigation is often done with the assumption that people in developing countries are acting irresponsibly and their behavior must be corrected by more enlightened conservationists from North America , Europe , and northern Asia . An analysis of the history of different land management practices shows that environmental degradation was often the result of colonial disruption of indigenous peoples. In the 1990 book Green Development by W.M. Adams, sustainable development is defined as practices designed to protect the environment and involve communities in making decisions. Land management practices developed by indigenous communities offer the best chance for sustainable development in Latin America today. Pre-Columbian land management practices in Latin America A diversity of cultures flourished in the Caribbean , Central and South America , before European conquistadors arrived, changing and using the land and resources to feed communities, build cities, raise temples, and govern empires. Land management practices were developed to be specific to their regions over the course of thousands of years in human communities. Prescribed burns were used in the pà ¡ramo of Costa Rica to promote desired kinds of vegetation (Horn, 1998). Raised fields created in the swamps of Mexico, Colombia , and Ecuador yielded large harvests (Atkins, Roberts, and Simmons, 1998) (Yapa, 2003). In the Venezuel... ...ly human fire mastery revealed.† BBC News Online. Retrieved from http://news.bbc.co.uk/2/hi/science/nature/3670017.stm Shetler, Jan Bender (2004). â€Å"Sugar and the Industrial Era.†Environmental History Lecture. Goshen College . Sluyter, Andrew (2002). Colonialism and Landscape. Lanham , Md. : Rowman & Littlefield Publishers. Watts , Sheldon (1999). Epidemic and History: Disease, Power and Imperialism. New Haven , Conn. : Yale University Press. Yapa, Kashyapa A. S. (2003, July 1). â€Å"Floodwater Management, The American Way †: Past and Present.† The Diary of a Polit-Eco Tourist. Retrieved November 7, 2004 , from http://kyapa.tripod.com/agengineering/drainage-lowland/drainage.htm Zimmerer, Karl S. And Kenneth R. Young, eds. (1998). Nature's Geography: New Lessons for Conservation in Developing Countries. Madison , Wis. : The University of Wisconsin Press. Sustainable Land Management in Latin America Essay -- Environment Envi Sustainable Land Management in Latin America â€Å"The enthusiastic celebration of indigenous skills can be the basis of alternative strategies of development.† – W.M. Adams Introduction The sustainability of land management practices in developing countries is in question currently as a way to address poverty. Yet, this investigation is often done with the assumption that people in developing countries are acting irresponsibly and their behavior must be corrected by more enlightened conservationists from North America , Europe , and northern Asia . An analysis of the history of different land management practices shows that environmental degradation was often the result of colonial disruption of indigenous peoples. In the 1990 book Green Development by W.M. Adams, sustainable development is defined as practices designed to protect the environment and involve communities in making decisions. Land management practices developed by indigenous communities offer the best chance for sustainable development in Latin America today. Pre-Columbian land management practices in Latin America A diversity of cultures flourished in the Caribbean , Central and South America , before European conquistadors arrived, changing and using the land and resources to feed communities, build cities, raise temples, and govern empires. Land management practices were developed to be specific to their regions over the course of thousands of years in human communities. Prescribed burns were used in the pà ¡ramo of Costa Rica to promote desired kinds of vegetation (Horn, 1998). Raised fields created in the swamps of Mexico, Colombia , and Ecuador yielded large harvests (Atkins, Roberts, and Simmons, 1998) (Yapa, 2003). In the Venezuel... ...ly human fire mastery revealed.† BBC News Online. Retrieved from http://news.bbc.co.uk/2/hi/science/nature/3670017.stm Shetler, Jan Bender (2004). â€Å"Sugar and the Industrial Era.†Environmental History Lecture. Goshen College . Sluyter, Andrew (2002). Colonialism and Landscape. Lanham , Md. : Rowman & Littlefield Publishers. Watts , Sheldon (1999). Epidemic and History: Disease, Power and Imperialism. New Haven , Conn. : Yale University Press. Yapa, Kashyapa A. S. (2003, July 1). â€Å"Floodwater Management, The American Way †: Past and Present.† The Diary of a Polit-Eco Tourist. Retrieved November 7, 2004 , from http://kyapa.tripod.com/agengineering/drainage-lowland/drainage.htm Zimmerer, Karl S. And Kenneth R. Young, eds. (1998). Nature's Geography: New Lessons for Conservation in Developing Countries. Madison , Wis. : The University of Wisconsin Press.

Does Population Growth Affect Economic Growth? Essay

Population growth has its own effects on economic growth of a country, which can be negative or positive first we will look in to the negatively effecting factors of population growth: 1) Due to increase in Population Consumption Increases, which will decrease, GNP/GDP and Imports will increase and Exports Fall down Budget Defect is the result and the prices mount high. 2) Miss Use OR Over use of Natural Resources. Due to increase in population Man to Land Ratio decreases. As land is inelastic, one cannot increase the amount or supply of land. 3) Raw-Material or Primary Goods are used or processed directly or indirectly which produce finished goods and yield residues some of it is recycled and some is disposed to nature, which effects it negatively. Therefore, when more and more people depend on land there are more chances of the damage accruing to ecosystem. 4) Effect on PCI, if the population growth does not match the labor force there is a negative effect on PCI. 5) Population Growth and Standard of Living, as increase in population leads to more consumption. ALTERNATIVELY, there are more mouths to feed which effects the standard of living. 6) Population and Agriculture, the pressure on land increases and increase disguised unemployment. 7) Population and employment, unemployment increases due to increase in population. 8) Population and Social infrastructure, pressure increases, as one Doctor has to attend more and more patients similarly in other fields also. 9) Population Increase decreases Capital Formation. 10) Population Increase results in Brain Drain. 11) Population Increase negatively effects Environment as urban slums increase.

It was about two in the morning and everyone has went to...

It was about two in the morning and everyone has went to bed. I was awake, the house was so quite, I could hear everyone breathing. Elena and Andrea where sleeping on my bed with me. I was sitting at the foot of my bed watching Elena and Andrea sleep. It felt as if I was still going to cry even hours after everything. Wondering if they were going to show this part on T.V. or leave it out. Wondering if they were even going to keep the show going after this. Thinking I heard a door open, my heart speed up. What if... a scream almost left my lips when I see Zayn poke his head around the door looking in. He just looks at me, then holding out his hand for me to come. Slowly, I get up, taking him hand, letting him lead me. He walks us to the†¦show more content†¦He glared at her. I did my best to act like nothing was wrong or going on; that was the truth. â€Å"Do you mind?† I said to Louis who was standing right in front of me. He stepped to the side, so I could stand up. â€Å"Thank you.† I said, looking at Zany, he smiled. Starting to walked off I heard Andrea say â€Å"Wait of me.† I looked back, Zayn was running his hand throughout his hair, rubbing his eyes. â€Å"So?† Andrea said, smiling at me. Walking into our room I could feel her watching me. â€Å"Where have you to been?† Elena said, then adding, â€Å"Where are you dress and Zoey isnt?† Andrea looked around the room. â€Å"Is it just us?† she whisper. Elena shock her head no. I took this chance to sneak out of the room. Louis and Zayn were right where we left them. Right before I opened the glass door I could see my refection, I was in my pjs tank top and shorts, my hair as a bit messy; not really caring I open the door. Walked out. Walking off I toss my hair up in a ponytail. Do a few quick stretches. Then take off running. I havent been running in weeks. Part way down the beach I can hear my name being called so I stop running. Elena and Andrea where walking, seeing Elena cant run. Waiting for them to get closer I sit. I couldnt see the house any more. Once they got to me they just look at me, sitting down. I just look at them back. â€Å"Did she tell you?† I asked. The sun was shining, the wind was softly blowing as the two girl nod their headsShow MoreRelatedMitochondrial Pathway Of Mitochondrial And Mitochondrial Permeability Transition977 Words   |  4 Pagesdefined by the presence of conserved Bcl-2 homology domains (BH1 to BH4). Up to 30 Bcl-2 family genes have been identified in mammals, which have either pro-apoptotic or anti-apoptotic functions. Some of the anti-apoptotic members include Bcl-2 itself, Bcl-XL, Bcl-w, BAG and Mcl-1 which possess all domains of BH1 to BH4. The pro-apoptotic family proteins can be divided into two subgroups: consists of Bak, Bax, and Bok with possess BH1 to BH3 domains, and Bad, Bid, Bik, BNIP3, Bim, Bmf, Blk, Hrk,Read MoreBcl-2 Protein Essay790 Words   |  4 Pagespro-apoptic proteins BAK and BAX, which undergo oligomerization that lead to outer mitochondrial membrane (OMM) permeabilization and cytochrome c release. This, in turn, triggers caspase activation and promotes cell death (6, 7). This inhibi tion occurs by BH1-BH3 domains of Bcl-2, which they form a hydrophobic pocket binding and inhibiting BH3- only protein (Bim), consequently preventing the activation of BAK and BAX (8). Second, BCL-2 targets the inositol 1, 4, 5-trisphosphate receptor (IP3R) through itsRead MoreDevelopment Of BL 2 And BCL XL Case Study1393 Words   |  6 Pagesdevelopment of haematological cancers. The family includes pro-apoptotic members (which promote cell death) and anti-apoptotic or pro-survival members (which prevent cell death) which are then categorised based on the number of BCL-2 homology domains (BH1, BH2, BH3, BH4) they share4, (for example the anti-apoptotic proteins BCL-2 and BCL-XL share very similar BH3 domains). They all share a similar general fold consisting of two central hydrophobic ÃŽ ±-helices surrounded by six or seven amphipathic ÃŽ ±-helices4