Homo habilis (sh) and formyl peptide (medicine)

Homo habilis (sh)

(Latin; "dexterous man")

Extinct species of early hominid that inhabited parts of sub-Saharan Africa 2.

5-1.5 million years ago and is generally regarded as the earliest member of the genus Homo. H. habilis remains were first discovered in 1959 and 1960 at Olduvai Gorge in northern Tanzania; additional remains have since been found in the Lake Turkana region of northern Kenya and, arguably, at Sterkfontein in South Africa. The cranial capacity of H. habilis ranged from 600 to 800 cc. Limb bones suggest that the species walked efficiently bipedally, and the fossil of a hand suggests that H. habilis was capable of precise manipulation of objects. Crude tools found along with H. habilis remains provide further evidence that this species could shape stone. See also human evolution; Oldowan industry.

formyl peptide (medicine)

formyl peptide
<biochemistry> Informal term for small peptides with a formylated N terminal methionine and usually a hydrophobic amino acid at the carboxy terminal end (fMetLeuPhe is the most commonly used).

These peptides stimulate the motor and secretory activities of leucocytes, particularly neutrophils and monocytes, that have a specific receptor (about 60 kD) of high affinity (Kd approximately 10exp 8M).

Leucocytes show chemotaxis towards formyl peptides but the term chemotactic peptides understates the range of activities the molecules will trigger. Thought to be synthetic analogues of bacterial signal sequences though this is unproven. The leucocytes of many animals (e.g. Pig, cow, chicken) do not respond.

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