Showing papers in "Annual Review of Biochemistry in 1969"

DNA Modification and Restriction

Abstract: Publisher Summary This chapter discusses the interaction of restriction endonucleases with double-stranded DNA molecules at specific sites leading to cleavage of the DNA into a number of fragments. The specificity of this interaction is thought to depend on the recognition by the enzyme of a particular sequence of base-pairs on the substrate DNA. Restriction endonucleases are found in many bacterial strains as products of genes carried either on the bacterial chromosome or on plasmid DNA. Among enzymes obtained from independent sources, each usually shows its own specificity of interaction. The chapter describes that a bacterial strain can protect its own DNA from cleavage by its restriction endonucleases. This protection is brought about by site-specific methylation of the DNA, for which another activity, the DNA modification methylase, is responsible. Both endonuclease and methylase are thought to recognize the same base sequences on their substrate DNA. Each independent system of restriction and modification activities would then recognize its own particular target on the DNA. Therefore, the modification given by a particular methylase protects the DNA only against restriction by the correlated endonuclease. The chapter also discusses that mostly for reasons of a historical and practical nature, laboratory strains such as Escherichia coli K12 and B or Haemophilus influenzae are widely used in the experimental investigation of DNA restriction and modification, although many other bacteria are either known or are likely to have restriction and modification systems.

Oxidative Phosphorylation in Mitochondria

Abstract: INTRODUCTION. • • • • • • • • • • • • • • • • • • • • • • • • • • • • . • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 991 ELECTRON TRANSPORT AND COUPLING SITES. • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 991 PROTEIN FACTORS THAT COUPLE RESPIRATION WITH PHOSPHORYLATION. • • • • • • • • • • 999 Phosphoryl tran�rerases. . . . . . . . • . . . . • . . . . . . . • . . . • . • . . . . . . . . . . . . . . . . . • . . . .. 999 Energy transfer factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1002 Oligomycin-sensitizing factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • • . . . . . . . . • . . . 1003 ENZYME DISTRIBUTION WITHIN MITOCHONDRIA. • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 1004 TRANSPORT OF IONS IN RELATION TO ENERGY COUPLING • • • • • • • • • • • • • • • • • • • • • • • 1009 General permeability properties of the mitochondrion. . . • . . . . . . . . . . . . . . . . . . . . . .. 1010 Anion transport.. . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . .. 1010 Energy dependence oj transport . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1012 Involvement of ion transport in the mechanism of uncoupling . . . . . . . . . . . . . . . . . . . . 1014 HYPOTHETICAL MECHANISMS AND MODEL REACTIONS • • • • • • • • • • • • • • • • • • • • • • • • • " 1017 Oxidation of thioethers • • • • • • • • • • • . • • • • •• • • • •• • • • • • •• • • • •. , • • • , •...•.•• 1019 DATA BEARING ON MECHANISMS • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 1021 Chemiosmotic phenomena. . . . . . . . . . . . . • . • . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . .. 1021 NADH-->NADP+ transhydrogenase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1022 Exchange reactions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . .. 1023 Inhibitors and uncouplers . . . . . . . . . . . . . . .. . . . . . . . .. . . . . . . . .. . . . . . . . . . . . . . . . 1023 Phosphorylation of ADP 1024

Cell Membranes: Structure and Synthesis

Abstract: INTRODUCTION. . . . . • . . . . . . . . . . • • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 263 ISOLATION OF MEMBRANES . . . . . . . • . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 264 General comments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 Plasma membranes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 Endoplasmic reticulum. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265 Mitochondria. . . . . . . . . . . . .. . . . . . . . . . . .. . . .. . . .. .. . . . . . . . . . . .. .. . . . . . .. .. 265 Bacterial membranes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 267 MEMBRANE COMPOSITION. • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . 267 Generalcomments , 267 Plasma membrane and endoplasmic re ticulum . . 270 Erythrocyte ghost . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 270 Mitochondria , , . . . . . . .. . . ... 271 MEMBRANE ORGANIZATION , .. , 272 General comments , . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 272 Myelin , ......... , . . . . . . . . . . . . . . . . . . .. 273 Plasma membrane ,. . . . . . . . . . . . . . . . . . . . . . . . . .. ... 274 Erythrocyte ghosts . . .. . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 274 Mitochondria ,. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 275 Chloroplasts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 277 Bacterial membranes , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 MEMBRANE SYNTHESIS , ..... , .... , . . . . . . . . . . . . . . . . . . . 279 General comments . . . . . . . . . . . . . .. . , , . . . . . . . . . . . . . . . . . . . . . .. 279 Myelin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , ,.... 279 Plasma membrane , , . . . . . .. 279 Endoplasmic reticulum ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280 Mitochondria ....... , , , . . . . . . . . . 281 Chloroplasts , ..... , . . . . . . . . . . . . . . . . . . . . . . .. 283 CONCLUDING REMARKS, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283

Metabolism of Fatty Acids

Abstract: FATTY ACID OXIDATION. . • . • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • . • • . • • • • • • • • • • • • 159 a-Oxidation. • . . . . . . . . . . . . . . . . • . • • • . . . . . . . . . . . . . • • • . . . . • • . . . . . . . . . . . . . . . • 159 {3-0xidation.. . 162 Propionate metabolism . . . . . . . . . . . . . . ....... . .. . ... . . . . . .. '.' . . . . . . . . . . . . . . . 168 w.oxidations and hydroxylations. . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169 Lipoxidase. . . . . .. . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . .. .. . . . . 173

Chemical synthesis of peptides.

Abstract: Peptides are the long molecular chains that make up proteins. Synthetic peptides are used either as drugs (as they are biologically active) or in the diagnosis of disease. Peptides are difficult to make as the synthetic chemist must ensure that the amino acids that make up the chain are added in the correct order and that they don't undergo any other reactions. This involves adding one amino acid, washing away any unreacted acid then adding the next and so on. As can be imagined, this is very time consuming and only gives very low yields.