Specific interactions outside the proline-rich core of two classes of Src homology 3 ligands.

Two dodecapeptides belonging to distinct classes of Src homology 3 (SH3) ligands and selected from biased phage display libraries were used to investigate interactions between a specificity pocket in the Src SH3 domain and ligant residues flanking the proline-rich core. The solution structures of c-Src SH3 complexed with these peptides were solved by NMR. In addition to proline-rich, polyproline type II helix-forming core, the class I and II ligands each possesses a flanking sequence that occupies a large pocket between the RT and n-Src loops of the SH3 domain. Structural and mutational analyses illustrate how the two classes of SH3 ligands exploit a specificity pocket on the receptor differently to increase binding affinity and specificity.

Eukaryotic methionyl aminopeptidases: two classes of cobalt-dependent enzymes.

Using partial amino acid sequence data derived from porcine methionyl aminopeptidase (MetAP; methionine aminopeptidase, peptidase M; EC 3.4.11.18), a full-length clone of the homologous human enzyme has been obtained. The cDNA sequence contains 2569 nt with a single open reading frame corresponding to a protein of 478 amino acids. The C-terminal portion representing the catalytic domain shows limited identity with MetAP sequences from various prokaryotes and yeast, while the N terminus is rich in charged amino acids, including extended strings of basic and acidic residues. These highly polar stretches likely result in the spuriously high observed molecular mass (67 kDa). This cDNA sequence is highly similar to a rat protein, termed p67, which was identified as an inhibitor of phosphorylation of initiation factor eIF2 alpha and was previously predicted to be a metallopeptidase based on limited sequence homology. Model building established that human MetAP (p67) could be readily accommodated into the Escherichia coli MetAP structure and that the Co2+ ligands were fully preserved. However, human MetAP was found to be much more similar to a yeast open reading frame that differed markedly from the previously reported yeast MetAP. A similar partial sequence from Methanothermus fervidus suggests that this p67-like sequence is also found in prokaryotes. These findings suggest that there are two cobalt-dependent MetAP families, presently composed of the prokaryote and yeast sequences (and represented by the E. coli structure) (type I), on the one hand, and by human MetAP, the yeast open reading frame, and the partial prokaryotic sequence (type II), on the other.

Two classes of metric spaces

The class of metric spaces (X,d) known as small-determined spaces, introduced by Garrido and Jaramillo, are properly defined by means of some type of real-valued Lipschitz functions on X. On the other hand, B-simple metric spaces introduced by Hejcman are defined in terms of some kind of bornologies of bounded subsets of X. In this note we present a common framework where both classes of metric spaces can be studied which allows us to see not only the relationships between them but also to obtain new internal characterizations of these metric properties.

Ledger for the Classes of 1650-1663, 1649-1660

The leather-bound volume contains accounts for the Classes of 1650-1663 and Fellows. Many of the student bills were settled with payment in kind, often in the form of grain, apples, or livestock. The Steward's accounts with the College from 1656-1659 were entered on pages 295-303 and listed as "The steward is Creditor" and "The steward is Debitor." Credit entries include food, fuel, corn, and wages; debit entries list purchases and often identify the sellers.

Ledger for the Classes of 1703-1718, 1703-1731

The parchment-bound hardcover folio volume contains accounts for Fellows, Tutors, the President, and members of the Classes of 1703-1718. Payments were often made with bills of credit, money, and notes. The Steward's accounts with the College are interspersed in the volume.

Ledger for the Classes of 1723-1731, 1719-1755

The volume, bound in a modern leather binding, contains accounts for the Classes of 1723-1731. Leaves 108-118 list the Steward's account with Harvard College arranged monthly for the years 1721-1729.

Ledger for the Classes of 1732-1743, 1728-1749

The volume, bound in a modern green leather binding, contains accounts for the Classes of 1732-1743. The Steward's accounts with Harvard College are interspersed throughout the volume.

Ledger for the Classes of 1744-1749, 1733-1750

The volume, bound in a hardcover parchment binding, contains accounts for the Classes of 1744-1749.

Ledger for the Classes of 1795-1804, 1795-1804

The leather bound folio account book kept by Steward Caleb Gannett contains accounts for members of the Classes of 1795-1804, as well as accounts for President Joseph Willard, Tutors, Fellows, and Faculty. The volume also contains the Steward's accounts with the Harvard Treasurer, as well as his "Cash" accounting. The volume does not have the detailed transaction descriptions found in earlier ledgers; both Credit and Debit entries are described as being paid by, or being owed to, cash, balance, sundry accounts, or the Treasury.

Quarter bill book for the Classes of 1689-1723 and ledger, 1687-1720

Parchment hardcover bound volume arranged into two parts: Quarter bill book and the Steward's ledger. The Quarter bill book contains quarter bill tallies for the Classes of 1689-1723 arranged by seniority, and covers the bill period ending on October 21, 1687 through the period ending March 11, 1720.

Quarter bill book for the Classes of 1720-1760, 1720-1756

Parchment hardcover bound volume containing quarter bill tallies for the Classes of 1720-1760 arranged by seniority, and covering the bill period ending on June 10, 1720 through the period ending December 10, 1756. After each quarter's tallies, an additional section provides the totals for all students in each of the categories, and deductions for building repairs.

Quarter bill book for the Classes of 1757-1773, 1757-1769

Parchment hardcover bound volume containing quarter bill tallies for the Classes of 1757-1773 arranged first by seniority, and later alphabetically, and covering the bill period ending on March 11, 1759 through the period ending December 8, 1769. Billing categories are occasionally added or removed in the volume, including a Hebrew Grammar category in 1764, and one for the Hancock Professor in 1765. After each quarter's tallies, an additional section provides the totals for all students in each of the categories, and deductions for building repairs.

Quarter bill book for the Classes of 1770-1787, 1770-1789

Leather hardcover bound volume containing quarter bill tallies for the Classes of 1770-1787 arranged alphabetically and covering the bill period ending on March 9, 1770 through the period ending February 27, 1784. After each quarter's tallies, an additional section provides the totals for all students in each of the categories.

Quarter bill book for the Classes of 1776-1779, 1775

Three folded sheets containing quarter bill tallies for the Classes of 1776-1779 for the quarters ending on March 1775, June 1775, and September 1775, with totals for all students in each category also provided.

Quarter bill book for the Classes of 1784-1801, 1784-1797

Leather hardcover bound volume containing quarter bill tallies for the Classes of 1784-1801 arranged alphabetically and covering the bill period ending on May 27, 1784 through the period ending on November 23, 1797. After each quarter's tallies, an additional section provides the totals for all students in each of the categories, and "Orders on the above bill" listing individuals, including the Butler and sweepers, paid with the money.