The mechanism of formation of gels from myosin molecules

Journal of the Science of Food and Agriculture - Tập 58 Số 1 - Trang 63-73 - 1992
Alan H. Sharp1, Gerald Offer2,3
1Muscle Biology Department, AFRC Institute of Food Research—Bristol Laboratory, Bristol BS18 7DY, UK
2Muscle Biology Department, Langford, Bristol BS18 7DY, UK
3The Bristol Laboratory of the AFRC Institute of Ford Research was closed in December 1990

Tóm tắt

AbstractHeat‐set myosin gels form the basis of the adhesive that binds particles of meat together in meat products. The manner in which a gel network is formed from myosin has been investigated by studying the aggregates produced when dilute solutions of rabbit skeletal myosin molecules in 0.6 M KCI, 20 mM potassium phosphate, pH 6.5, were heated at a single temperature between 30 and 60°C. The aggregates have been examined by transmission electron microscopy after either negative staining or rotary shadowing.After heating at 30°C for 30 min. no change in structure is detected. After heating at 35°C for 30 min, the two heads of some myosin molecules coalesce and some dimers are formed by aggregation through the heads. After heating at 40°C for 30 min. up to about 13 myosin molecules aggregate through their heads to form a globular mass up to 60 nm across with the tails radiating outwards. At higher temperatures such head‐linked oligomers aggregate further. At 48°C oligomers coexist with aggregates formed by the coalescence of two or more oligomers. In such aggregates the globular masses are in close proximity and tails radiate from them. After heating myosin at 50°C, aggregates are formed by the coalescence of more oligomers and the tails are seen only indistinctly. At 60°C the particles formed contain a large number of globular masses and are typically 100 to 200 nm across, occasionally up to 1 μm. It is possible that the globules making up the strands of the gel networks in scanning electron micrographs are composed of similar particles. It is suggested that these globules are formed by head‐head interactions but that tail‐tail interactions may be important in forming the strands and cross‐links of the gel network.When a heat‐set myosin gel is compacted by centrifugation, the supernate contains essentially all the LC1 and LC3 light chains of the parent molecule but only a small fraction of the LC2 light chains. We suppose that dissociation of the LC1 and LC3 chains from the heads creates hydrophobic patches which cause intramolecular and intermolecular head association.

Từ khóa


Tài liệu tham khảo

10.1007/BF00711931

10.1002/jsfa.2740051005

10.1016/0003-9861(60)90130-2

10.1021/bi00728a020

10.1042/bj0750530

10.1111/j.1432-1033.1984.tb08553.x

10.1101/SQB.1973.037.01.008

10.1016/0022-2836(78)90204-8

10.1098/rspb.1976.0030

Gazith J, 1970, Studies on the submit structure of myosin, J Biol Chem, 245, 15, 10.1016/S0021-9258(18)63416-7

Gershman L C, 1969, Subunit structure of myosin. 3. A proposed model for rabbit skeletal myosin, J Biol Chem, 244, 2726

Hamm R, 1978, Protein solubility and water binding under the conditions obtaining in Brühwurst mixtures. II. The effects of heat on dissolved proteins, Fleischmirtschaft, 58, 1257

10.1016/B978-0-12-516304-0.50008-8

Hellendoorn E W, 1962, Water‐binding capacity of meat as affected by phosphates. 1. Influence of sodium chloride and phosphates on the water retention of comminuted meal at various pH values, Food Technol, 16, 119

Hermansson A‐M, 1986, Functional Properties of Food Macromolecules, 273

10.1016/B978-0-408-02950-6.50008-X

10.1002/jsfa.2740420409

10.1002/jsfa.2740370111

10.1016/0003-9861(56)90294-6

10.1111/j.1365-2621.1979.tb06419.x

10.1042/bj0740432

10.1016/0006-3002(61)90446-2

10.1016/B978-0-408-02950-6.50018-2

JolleyP D.SavageA W J1985Proc Reiner Hamm Symp Current Meat Research Vol 91. Mitteilungsblatt Bundes‐anslalt Fleischforsch Kulmbach. pp6781–6788.

Knight P, 1987, Fibrous Protein Structure, 247

Kotter L, 1975, The influence of phosphates or polyphosphates on the stability of foams and emulsions in meat technology, Fleischwirtschaft, 55, 365

Lacmmli U K, 1970, Cleavage of structural proteins during the assembly of the head of bacteriophage T4, Nature, 227, 680, 10.1038/227680a0

10.1038/175389a0

10.1016/0006-3002(56)90345-6

10.1016/0006-3002(59)90568-2

10.1021/ja01515a027

10.1111/j.1365-2621.1977.tb08437.x

10.1016/0022-2836(83)90053-0

10.1016/0889-1605(85)90077-1

10.1111/j.1745-4603.1971.tb00274.x

Offer G, 1988, Developments in Meat Science—4, 63

OfferG.PurslowP.AlmondR.CousinsT.ElscyJ LewisG.ParsonsN SharpA StarrR KnightP1988Myofibrils and meat quality.Proc 34th Int Cong Meat Sci Technol Brisbane pp161–168

Offer G, 1989, The structural basis of water‐holding, toughness and appearance of meat, Food Microstructure, 8, 151

10.1016/0003-9861(52)90258-0

Pastra‐Landis S C, 1986, Myosin subunit interactions. Properties of the 19000‐dalton light chain‐deficient myosin, J. Biol Chem, 261, 14811, 10.1016/S0021-9258(18)66944-3

10.1042/bj1040609

Pern S V, 1955, Methods in Enzymology, 582

10.1021/bi00400a032

10.1271/bbb1961.40.2455

10.1111/j.1365-2621.1981.tb04187.x

10.1271/bbb1961.47.2373

Schmidt G R, 1982, Proc Int Symp Meat Sci Technol, 265

Sherman P, 1961, The water binding capacity of fresh pork. I. The influence of sodium chloride, pyrophosphate and polyphosphate on water absorption, Food Technol, 15, 79

10.1111/j.1365-2621.1979.tb03463.x

10.1016/0022-2836(86)90003-3

10.1021/bi00564a035

Swift C E, 1956, The action of phosphates in sausage products. 1. Factors affecting the water retention of phosphate‐treated ground meat, Food Technol, 10, 546

10.1016/0003-9861(62)90241-2

Trautman J C, 1966, The Physiology and Biochemistry of Muscle as a Food, 403

10.1111/j.1365-2621.1966.tb00514.x

10.1111/j.1365-2621.1972.tb05837.x

10.1016/0006-291X(60)90042-5

10.1016/0022-2836(86)90283-4

10.1016/0022-2836(85)90300-6

10.1016/0022-2836(71)90074-X

10.1002/jsfa.2740350317

10.1271/bbb1961.52.1803

10.1016/0003-9861(60)90122-3

10.1111/j.1365-2621.1979.tb03481.x

10.1111/j.1745-4514.1980.tb00646.x

Thông tin
Thông tin xuất bản

Journal of the Science of Food and Agriculture

Tập 58 Số 1

63-73

Thông tin tác giả