Exam 2 - Vitamin B6, B7

what is the name of vitamin B6

pyridoxal phosphate (PLP)

each vitamer of pyridoxal phosphate (PLP/B6) will start with what

pyrox-

what are some coenzyme functions of pyridoxal phosphate (PLP/B6)

AA metabolism

glycogen degradation

synthesis of HEME

myelin sheath

what are some functions of the noncoenzyme form of pyridoxal phosphate

facilitate binding of steroid hormones for gene expression

describe the relationship between intake of protein and requirement of B6

more protein intake = more B6 required

what are sources of pyridoxal phosphate (PLP/B6)

enriched grains, meats, nuts, grains

what are some s/s of pyridoxal phosphate (PLP/B6) deficiency

dermatitis, glossitis, cheilosis, stomatitis, peripheral neuropathy, hypochromic microcytic anemia

what deficiency is commonly found with a pyridoxal phosphate (PLP/B6) deficiency

folate

vitamin B6 toxicity leads to damage of what

nerves

what is the name of vitamin B7

biotin

what form of biotin (B7) is found in food

biocytin

biotin (B7) is bound to several ____ for FA synthesis, gluconeogenesis, metabolism of propionate and leucine

carboxylases

the non-coenzyme form of biotin (B7) functions in ___ expression through transcription of several enzymes

gene

what are some biotin-dependent enzymes

pyruvate carboxylase

acetyl-coa

propionyl-coa carboxylase

beta-methylcrotonyl-coa carboxylase

CARBOXYLASES

biotin (B7) plays a role in the krebs cycle by converting ___ to _____

pyruvate, oxaloacetate

what step is biotin (B7) a part of in FA synthesis

committed step

synthesis of malonyl coa

what are some sources of biotin (B7)

bacteria in LI

widely distributed in food

what is a potent binder of biotin (B7) and can lead to raw egg white injury due to its presence in raw egg whites

avidin

what are some s/s of biotin (B7)

dermatitis, anorexia, depression, alopecia, muscle pain, lethargy

a genetic condition of inborn error of metabolism of biotin can lead to what

biotinidase deficiency - screened for at birth

who is at risk for biotin (B7) deficiency

chronic alcoholics, those who eat excessive raw egg whites, pregnant and breastfeeding women

there is no toxicity associated with biotin (B7), but high dose supplementation can affect lab data from ___ and ___ tests

thyroid, vit d