Question

hehe instructions: You may work on this individually or in groups. Remember you will each be responsible for knowing the material individually on exam. Please write answers on separate sheet where appropriate. This will be turned at end of class Thursday Oct. 31. credit will be based on combination of participation and attendance. You may pick up your copy of answers outside my office Friday morning and/or view key after class on Blackboard. These are good study questions for your exam. h tul tren har for the Drawing Carbohydrates 1. Draw the structural formula for a-D-glucosyl-(1 6)-D-mannosamine. Number all carbons. Mannoseamine refers to 2-amino-2-deoxymannose. a. Circle the hemiacetal functional group. Given the presence of a hemiacetal group, would this be a non-reducing or reducing sugar? Mark with a squiggly line over the b ond broken corresponding to a ring opening. b. Add asterisk next to anomeric carbon(s). HOOH c. Which carbons form acetal functional group(s)? HO 2. Gentiobiose (D-Glucose($16)D-Glucose) is a disaccharide found in some plant glycosides. Draw the structure of gentobiose based on its abbreviated name. Is it a reducing sugar? OJO Does it undergo mutarotation? O Enzyme Mechanisms 3. Several amino acids can be involved in general acid-base catalysis. Draw a representative amino acid for the following conditions and provide 1 letter code: a. Proton donor from carboxylic acid LOT b. Base from thiolate una tromleylanabrid smislo zbum r art 2 c. Acid form of an amino acid that is also frequently phosphorylated ml sitini 1999 d. Proton donor from amino side chain e. Proton acceptor from carboxylate bidw y d basimili notubong bad namanyly lo 9167 z'brid smag o g 4. Draw a nucleophilic attack for the following simplified reactions coulommor bild smag 5 gol Won Triglwyd nogovia . Tuodsning yozu ozum Parts ni sub-C o lom 93615VOMA) y no What type or post-translation 10-Hols phogphorylase and glycoger ö b ö respon n t hulls 25 Viz yoman lolo bylode ser a Adenine Ribose-o-o-o-o-o-o-o- HÖ-R on 1959 w molto lobozogmoo zabharbaszoglo 10 2 0-bbo- n o - vilo Glucose nila ATP919bhaboszonom intellid O

Answer 1

Acetal functional group 6 ОН , он а -D-glucosyl-(1-->6)-D-Mannosamine 4 он на нен 2 оно la 6. и 5 а-(1-->6) glucosidic linkage —он S a reducing sugar на 1 он 2) It undergoes mutarotation because it has open hemiacetal group. OH о. В-(1-->6) glucosidic linkage н —о н —о он 1a reducing sugar нон Н ОН | HONOH ucing sugar H

3) a) proton donor from -COOH: to a C00 O +NH3 (S)-(+)-Aspartic Acid (Asp, D) 3) b) base from thiolate: HS HS Coo +NH3 (R)-(-)-Cysteine (Cys, C) c) often phosphorylated: HoCoo- +NH3 (S)-(-)-Serine (Ser, S)

d) proton donor from amino side chain: Coo- I + +NH3 Z (S)-(-)-Histidine (His, H) e) proton acceptro from carbo) N+ coo Hн (S)-(-)-Proline (Pro, P) 4) Electron flow from rich to poor. -Sinisubir To-H type o stranslatok horylase and glycogen ÖR

bilulla scenisz yom an O O O Adenine - Ribose -------- HÖ-R obozoomob novno stog do 20 oso-vilo Glucose ATD91 b onomo