In an intriguing series of experiments carried out many years ago, a common scientific belief, feted by no less than three Nobel prizes, was brought into question. The observations were about proteins-the molecules that the genetic code specifies and that are in one way or another central to all of life''s activities. The experiments however were not about what proteins do, but how they are moved, in particular how they are moved from where they are made to where they act. The results of these studies conflicted with the standard view of how this happens, and thus became controversial.
The standard view, the vesicle theory of protein secretion, envisions proteins being carried within and out of cells en masse in membrane-bound sacs or vesicles. The controversial experiments demonstrated that to the contrary individual protein molecules cross the relevant membranes as a result of their own motion. This was thought to be impossible at the time. Proteins Crossing Membranes is a personal narrative that tells the story of the controversy. Among other things, the author illustrates that scientists, like the rest of us, can rigidly hold onto their beliefs despite evidence that they are misguided.
- Reviews the data in support and critical of the vesicle theory of protein secretion
- Explores the ways scientists respond to evidence that challenges a favored theory
- Documents the author''s personal experiences in this conflict-laden situation
- Bytt i alle våre butikker
- Klikk og hent
Katika mfululizo wa majaribio ya kuvutia yaliyofanywa miaka mingi iliyopita, imani ya kawaida ya kisayansi, iliyosherehekewa na tuzo tatu za Nobel, iliulizwa swali. Uchunguzi huo ulihusu protini - molekuli ambazo kanuni ya maumbile hufafanua na ambazo kwa njia moja au nyingine ni muhimu kwa shughuli zote za uhai. Hata hivyo, majaribio hayo hayakuwa juu ya nini protini hufanya, lakini jinsi wao ni kusafirishwa, hasa jinsi wao ni kusafirishwa kutoka ambapo wao ni kufanywa kwa ambapo wao kutenda. Matokeo ya masomo hayo yalipingana na maoni ya kawaida ya jinsi jambo hilo linavyotukia, na hivyo yakawa yenye kubishaniwa. Nadharia ya vesicle ya secretion ya protini inaonyesha kwamba protini zinachukuliwa ndani na nje ya chembe kwa wingi katika mifuko au vesicles iliyounganishwa na utando. Majaribio hayo ya kutatanisha yalionyesha kwamba, kinyume chake, molekuli za protini zinazovuka utando huo kwa mwendo wao wenyewe. Wakati huo ilidhaniwa kwamba hilo halingewezekana. Protini Kupita Membranes ni hadithi ya kibinafsi ambayo inaelezea hadithi ya utata. Miongoni mwa mambo mengine, mwandishi anaonyesha kwamba wanasayansi, kama sisi wengine, wanaweza kushikilia kwa uthabiti imani zao licha ya uthibitisho kwamba wamepotea. - Huchunguza data katika msaada na muhimu ya nadharia vesicle ya protini secretion - Kuchunguza njia wanasayansi kujibu ushahidi kwamba changamoto nadharia favored - Hati ya mwandishi'uzoefu binafsi katika hali hii mgogoro-laden - Bytt i alle våre butikker - Klikk og hent