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The image below has been excised from a publication describing the composition of blood proteins. The feature in the structure that the arrow is pointing out is a __________, which is a ______ type of bond between _____ atoms.

The vertebrate fatty acid synthase is a large homodimeric, multifunctional enzyme consisting of two polypeptides, each containing a series of catalytic domains located along the linear primary structure, as depicted in the figure below (a schematic of a single polypeptide is shown; each domain is depicted as a rectangle on the linear polypeptide). Polyketides (PK) and nonribosomal polypeptides (NRP) are two molecular families of natural products biosynthesized by many plants, bacteria, and fungi. Polyketides and nonribosomal peptides have received considerable attention because they typically demonstrate antimicrobial activity, making them attractive molecules for the development of novel antibiotics. The type I polyketide synthases are analogous to the vertebrate fatty acid synthases, in both the organization (topology) of the protein’s primary sequence and in terms of the catalytic mechanism/chemistries. A phosphopantetheinyl transferase (Ppan transferase) is required to activate a fatty acid synthase, polyketide synthase, and nonribosomal peptide synthase, by attachment of a phosphopantetheine prosthetic group. The following are excerpts from a fairly recent publication: In enzymes such as fatty acid synthases, polyketide synthases, and nonribosomal peptide synthases, acyl groups (see below) are tethered to the phosphopantetheine arm’s sulfhydryl moiety via what type of linkage? 

The following information has been extracted from this 2001 research publication:Binding assays in this investigation were performed as follows:The table below summarizes the results of the binding assay.In light of the information above, which of the following accurately describes the outcome of this investigation? 

The single letter abbreviation for the amino acid with the side chain –CH2-COO- is:

The following data were obtained in a study of an enzyme known to follow Michaelis-Menten kinetics:The KM for this enzyme is approximately:

The amino acid shown below is: 

Question 3  A 35-year-old woman presents to the GP after feeling unwell for several months. She is experiencing worsening fatigue, weight gain and sensitivity to the cold. Based on the following thyroid function test results, identify the primary thyroid disorder present (10%), explain the biochemical mechanisms underlying this thyroid disorder (20%), and discuss the expected clinical symptoms that may be present in a patient with this thyroid disorder (10%). Evaluate the methods used to assess thyroid function including any additional tests you might perform to confirm a diagnosis (60%). TSH (Thyroid-Stimulating Hormone): 8.5 mIU/L (Reference Range: 0.4 – 4.0 mIU/L)  Free T4 (Thyroxine): 0.7 ng/dL (Reference Range: 0.8 – 1.8 ng/dL)  Free T3 (Triiodothyronine): 1.9 pg/mL (Reference Range: 2.3 – 4.2 pg/mL)   

Question 5  A 27-year-old male is brought to A&E on a Saturday afternoon in an incoherent state. Laboratory data from this patient reveals a Blood Alcohol Concentration (BAC) of 0.25%. Use this information and the patient’s serum data below to discuss the biochemical effects of alcohol toxicity (50%). Evaluate methods of analysis for alcohol toxicity and other drugs of abuse (50%). Sodium (Na+): 135 mEq/L (Reference Range: 135 – 145 mEq/L) Potassium (K+): 3.2 mEq/L (Reference Range: 3.5 – 5.0 mEq/L) Chloride (Cl-): 95 mEq/L (Reference Range: 98 – 106 mEq/L) Bicarbonate (HCO3-): 18 mEq/L (Reference Range: 22 – 26 mEq/L) Aspartate Aminotransferase (AST): 180 IU/L (Reference Range: 5 – 40 IU/L) Alanine Aminotransferase (ALT): 200 IU/L (Reference Range: 7 – 56 IU/L) Blood Urea Nitrogen (BUN): 8.1 mmol/L (Reference Range: 2.5 – 6.6 mmol/L) Creatinine: 1.8 mg/dL (Reference Range: 0.6 – 1.2 mg/dL) Blood glucose: 3.2 mmol/L (Reference Range: 3.9 – 5.6 mmol/L) Serum Osmolality: 326 mmol/Kg (Reference Range: 280 – 290 mmol/Kg)  

Which of the following correctly represents the change in Acetylcholine (ACh) levels when transferring between sleep stages and wake?

Explain Ridge and LASSO regularization in terms of Linear Regression.