BIOLCHEM 415 1st Edition Lecture 12 Outline of Last Lecture I. 7TM Signaling PathwaysII. Receptor messengers amplify signalsIII. Second messengers amplify signalsIV. Interference can lead to diseaseOutline of Current Lecture V. Monosaccharides are the simplest carbohydratesVI. Carbohydrates can attach to proteins forming glycoproteinsVII. Digestion cleaves large molecules for use in metabolismCurrent LectureMonosaccharides- simplest carboydrates- aldehyde/ketone with 2+ alcohol groups- exist in isomeric forms- ex- D-ribose, D-deoxyribose, D-glucoe, D-mannose, D-galactose, D-FructoseIntracellular bonds- chemical basis for ring formation- aldehyde reacts with alcohol to form hemiacetal- ketone can react with alcohol to from hemiketalMonosaccharides in open/cyclic forms- Hemiacetal creates other diastereoisomeric form, an ‘anomer’- linear form => ‘Fisher’These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- cyclic => ‘Hawarth’- chair or boat drawing more accurateDetecting glucose- aldehydes react with cupric ion- tests diabetes- reacts with hemoglobin in bloodOligiosaccharides and complex carbohydrates- oligosaccharide – contains 2+ monosaccharides linked by O-glycosidic bonds- can’t be broken down easily- can’t go through metabolism- cleaved by enzymePolysaccharides- glycogen/starch are storage forms of glucoseComplex carbohydrates- proteins and carbohydrates can create multifaceted polymers- glycoproteins - sugars + proteins and proteins > sugars- proteoglycans – large proportion of polysaccharides in to structure- mucoproteins – glycoproteins with amino-sugar contentBlood groups based on protein glycosylation patternsFood Fuel1) Digestion- large molecule smaller molecule2) Metabolism- small molecule to key metabolic moles3) Energy- ATP producedDigestion- begins in mouth- acidic stomach - denatures proteins- pepsin protease- small intestine- with pancreas- sodium bicarbonate to neutralize acid- bile salts to facilitate to digestion of fats- enzymes to digest all types of fuel moleculesProteases digest proteins into amino acids and peptides- components of digestive pathways secreted by small intestine, pancreas, and gall bladder- Secretin causes release of sodium bicarbonate- cholecystokinin (CCK) stimulates release of digestive enzymes from pancreas and bile salt from gall bladder- enzymes of stanch and pancreas secreted as inactive precurosrs- proenzymes or zymogens- zymogens are activated by proteolytic cleavageDietary carbohydrates are 1st digested by α-amylase- cleaves α-1,4 bonds but not α-1,6 bondsDietary fats degraded by intestinal lipases- into fatty acids and monoacylglycerol- absorption into the intestineBile salts combine with triacylglycerols - bile salts are amphipathic- can emulsify lipids- synthesized in liver and secreted by gallbladder- derived from cholesterol- lipases can digest emulsified fats- after digestion, triacylglycerols are resynthesized in intestinal mucosal cells and packaged into chylomicronsCell signaling regulates caloric homeostasis- GLP-1 and CCK signal fullness- long term control- leptin – stores fats and acts in brain- insulin reports on carb availability- failure obesity pathological
View Full Document
Unlocking...