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Home >> Dictionary of Bioinformatics, Biochemistry, Biotechnology >> Alcohol Fermentation Algal Biomass
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Albuminuria Presence of albumin in urine. albumin appears in urine in diseases associated with increased glomerular permeability. Albuminuria may be physiological or pathological. Physiological albuminuria is seen in adolescents, last trimester of pregnancy and severe stress. Orthostatic or postural albuminuria occurs in the upright position in young adults due to an increase in the hydrostatic pressure in the renal veins. It is however, a benign condition.
Pathological albuminuria is classified into prerenal, renal and postrenal causes. Prerenal albuminuria is due to impairment of renal circulation. Renal albuminuria is found in all forms of renal diseases. Postrenal albuminuria is due to lesions of renal pelvis, bladder and urethra.
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Alcohol fermentation The anaerobic conversion of glucose to ethanol via the glycolytic pathway.
Alcohol fuel An energy source produced by the process of bioconversion in which organic waste is converted to fuel by microorganisms.
Alcohol test A test for gastric function. After removal of gastric juice resting contents, 100 mL of 7% ethanol is given. The gastric contents are aspirated every 15 minutes up to 11/2 hours. Free acid is detected ¾ of an hour after alcohol ingestion, rises steadily reacting peak values 11/4 – 11/2 hours followed by a steady decline.
Alcoholic hepatitis Hepatitis seen in heavy drinkers after a bout of alcohol intake. Although the serum bilirubin concentration and transaminase activities are not much elevated, the clinical features resemble acute viral hepatitis. Markedly elevated plasma GGT activity together with an increase in uric acid and triglyceride levels is suggestive but not diagnostic of alcoholism. Alcoholic hepatitis may eventually progress to cirrhosis.
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Aldehyde A molecule with a doubly bonded oxygen and a hydrogen attached to the same carbon atom (HC=O).
Aldol The product of the condensation reaction between two ketones or an aldehyde and a ketone.
Aldolase A glycolytic enzyme that cleaves fructose 1,6-bisphosphate to glyceraldehyde 3-phosphate and dihydroxyacetone phosphate.
Aldose A simple sugar that has an aldehyde [ R-C(=O)-H] as the functional group.
Aldose reductase The enzyme that reduces galactose to the polyol, galactitol (dulcitol) in the lens.
Aldosterone A steroid hormone secreted by the adrenal cortex that influences Na+- K+ and Na+ -H+ exchange across all cell membranes. The hormone directly stimulates Na+ reabsorption by the renal tubular cells thereby increasing ECF volume.
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Aldosteronism Increased mineralocorticoid activity due to hypersecretion of aldosterone. Aldosteronism may be primary or secondary. In primary aldosteronism, hypersecretion of aldosterone is due to adrenal pathology, whereas, secondary aldosteronism is due to extraadrenal causes such as cirrhosis and nephritic syndrome. Hypersecretion of aldosterone causes increased sodium retention and potassium, excretion leading to hypokalaemia, hypertension, muscle weakness and fatigue. Hypokalaemia is caused by potassium wasting. There is also polyuria with compensatory polydipsia. Metabolic alkalosis occurs with elevation of plasma bicarbonate due to loss of H+ into urine and migration into the cells in exchange for K+. The adenoma can be localized can be localized by abdominal CT or MRI. Conn’s syndrome due to a tumour is surgically removed. Spironolactone, an aldosterone antagonist is administered patients with bilateral adrenal hyperplasia.
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Alga (pl. algae) A term used to refer to a group of simple, unicellular and multicellular eukaryotic photosynthetic organisms such as Nitella and Fucus. They are classified as Protista or plants according to their morphology. Algae are usually aquatic. While dinoflagellates and diatoms are free floating, the red and brown algae require a solid substrate for attachment. Based on their photosynthetic pigments, algae are further classified into brown, red, green and blue-green algae. Algae are used as thickeners for foods and bacterial culture media.
Alkane A hydrocarbon containing–CH3 and –CH2 groups.
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Algal biomass Single-celled plants, such as Chlorella spp. and Spirulina spp. that are grown commercially in ponds for the purpose of making feed materials especially for fish. This is a more convenient and controllable method of converting sunlight into food compared to normal farming.
Algicide A chemical agent such as copper sulphate which kills algae. Algicides are used in swimming pools.
Alginate A polysaccharide gelling agent.
Alcohol Polar organic molecule that contains a functional hydroxyl group attached to a carbon atom.
Alcohol dehydrogenase An enzyme responsible for catalysing the last step in alcoholic fermentation by yeast. The enzyme catalyses the conversion of ethanol to acetaldehyde.
Algorithm A series of steps defining a procedure or formula for solving a problem that can be coded into a programming language and executed. Bioinformatics algorithms are generally used to process, analyse, visualise, and store biological data as well as to make predictions from these data.
Alignment Comparison of two or more gene or protein sequences to determine the extent of base or amino acid similarity. Sequence alignments are used to determine the similarity, homology, function as well as the degree of relatedness between two or more genes or gene products.
Alignment score An algorithmically computed score based on the number of matches, substitutions, insertions and deletions within an alignment. The scores for matches and substitutions for proteins are derived from scoring matrices such as BLOSUM and PAM. The affine gap penalty suitable for the respective matrix is chose. Higher scores reflect better alignment.
Alimentary hyperinsulinism Excessive insulin secretion associated with hypoglycaemia that occurs following meals in patients after gastrectomy, vagotomy and gastrojejunostomy. This is due to rapid passage of food into the intestine and rapid absorption of glucose.
Aliphatic Containing – CH3 and –CH2 groups but lacking aromatic rings.
Alkalaemia Abnormal alkalinity of the blood.
Alkali A compound or solution of high pH.
Alkaline (basic) Having a pH of more than 7.0
Alkaline phosphatase (ALP) an enzyme that catalyses the removal of phosphate groups at alkaline pH. It is used in gene cloning to remove phosphate groups from vectors cleaved with restriction enzyme in order to prevent them from recircularising without gaining an insert.
Alkaloid Small, chemically complex nitrogen-containing metabolite synthesised by plants for defence against herbivores. Examples include caffeine and morphine. These are synthesised from the aromatic amino acids phenylalanine, tyrosine and trytophan.
Alkalophiles Microorganisms such as Vibrio cholerae and Agrobacterium that thrive in alkaline environments. These exist at a pH range of 7 – 12.
Alkalosis A pathological condition in which the pH of blood is increased.
Alkaptonuria The first human disorder recognised to be inherited as an autosomal recessive trait. It was recognised in the 16th century, characterised in 1859, and formed the basis for Garrod’s views on inborn errors of metabolism. Alkaptonuria is an inborn error of tyrosine metabolism characterised by a deficiency of homogentisate 1,2-dioxygenase that catalyses the conversion of homogentisic acid to maleylacetoacetic acid. Deficiency of the enzyme results in an accumulation of homogentisate in cells and body fluids with consequent excessive excretion in the urine. The darkening of urine on standing is a characteristic finding in alkaptonuria. Homogentisic acid undergoes oxidation and polymerisation to form alkapton, a grey to bluish-black pigment that gets deposited on connective tissues (ochronosis).
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