UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C. 20549
                                      
                                 SCHEDULE 13G
                                      
                  UNDER THE SECURITIES EXCHANGE ACT OF 1934
                                      
                         (AMENDMENT NO. _____3____)*
                                Enzon, Inc.                        
______________________________________________________________________________
                               (Name of Issuer)
                       Common
______________________________________________________________________________
                        (Title of Class of Securities)
                                  293904108
                         ____________________________
                                (CUSIP Number)

Check the following box if a fee is being paid with this statement 
___.  (A fee is not required only if the filing person:  (1) has a 
previous statement on file reporting beneficial ownership of more 
than five percent of the class of securities described in Item 1; 
and (2) has filed no amendment subsequent thereto reporting 
beneficial ownership of five percent or less of such class.) (See 
Rule 13d-7).

*The remainder of this cover page shall be filled out for a 
reporting person's initial filing on this form with respect to the 
subject class of securities, and for any subsequent amendment 
containing information which would alter the disclosures provided 
in a prior cover page.

The information required in the remainder of this cover page shall 
not be deemed to be "filed" for the purpose of Section 18 of the 
Securities Exchange Act of 1934 ("Act") or otherwise subject to 
the liabilities of that section of the Act but shall be subject to 
all other provisions of the Act (however, see the Notes).

                                         Page 1 of 3 pages
CUSIP NO. 293904108                
          ---------
                                     13G
______________________________________________________________________________
1   NAME OF REPORTING PERSON
    S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

            State of Wisconsin Investment Board
                39-6006423        
______________________________________________________________________________
2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP *
                                               (a)_____
            Not Applicable                             (b)_____
______________________________________________________________________________
3   SEC USE ONLY

______________________________________________________________________________
4   CITIZENSHIP OR PLACE OF ORGANIZATION

            Madison, Wisconsin
______________________________________________________________________________
                 5   SOLE VOTING POWER
  NUMBER OF                           2,271,000
   SHARES        _____________________________________________________________
BENEFICIALLY     6   SHARED VOTING POWER
  OWNED BY                            Not Applicable
    EACH         _____________________________________________________________
  REPORTING      7   SOLE DISPOSITIVE POWER
   PERSON                             2,271,000
    WITH         _____________________________________________________________
                 8   SHARED DISPOSITIVE POWER
                                      Not Applicable
______________________________________________________________________________
9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            2,271,000
______________________________________________________________________________
10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES  CERTAIN 
    SHARES *
            Not Applicable                                
______________________________________________________________________________
11  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9                
                        
            9.08%
______________________________________________________________________________
12  TYPE OF REPORTING PERSON *

            EP (Public Pension Fund)
______________________________________________________________________________

                    * SEE INSTRUCTION BEFORE FILLING OUT!

                              Page 2 of 3 pages


ITEM 1.  ISSUER
         (a)  Enzon, Inc.                                 
         (b)  40 Kingsbridge Road        
              Piscata Way, NJ. 08854
ITEM 2.  PERSON FILING
         (a)  State of Wisconsin Investment Board        
         (b)  P.O. Box 7842
              Madison, WI 53707
         (c)  Wisconsin State Agency
         (d)  See cover page
         (e)  See cover page

ITEM 3.  THIS STATEMENT IS FILED PURSUANT TO 13D-1(B) OR 13D-2(B) AND THE STATE 
OF WISCONSIN INVESTMENT BOARD IS A GOVERNMENT AGENCY WHICH MANAGES PUBLIC
PENSION FUNDS SUBJECT TO PROVISIONS COMPARABLE TO ERISA.

ITEM 4.  OWNERSHIP
         (a)  See Row 9 on Page 2
         (b)  See Row 11 on Page 2
         (c)  The State of Wisconsin Investment Board retains sole voting and 
              dispositive power for all shares.

ITEM 5.  IF THIS STATEMENT IS BEING FILED TO REPORT THE FACT THAT AS OF THE DATE
HEREOF THE REPORTING PERSON HAS CEASED TO BE THE BENEFICIAL OWNER OF MORE THAN
FIVE PERCENT OF THE CLASS OF SECURITIES, CHECK THE FOLLOWING ____.

ITEM 6.  NOT APPLICABLE

ITEM 7.  NOT APPLICABLE

ITEM 8.  NOT APPLICABLE

ITEM 9.  NOT APPLICABLE

ITEM 10. CERTIFICATION

        By signing below I certify that, to the best of my knowledge and belief,
the securities referred to above were acquired in the ordinary course of
business and were not acquired for the purpose of and do not have the effect of 
changing or influencing the control of the issuer of such securities and were
not acquired in connection with or as a participant in any transaction having
such purposes or effect.

                                  SIGNATURE
        
        After reasonable inquiry to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.
                                      
                              February 13, 1995
                          ___________________________
                                     Date
                                      
                                George Natzke
                          ___________________________
                                  Signature
                                      
                         George Natzke, Administrator
                          ___________________________
                                  Name/Title

                                 Page 3 of 3